Feb 2016

A trial bid is used when the bidding goes for example 1♠ (p) 2♠ (p) and you want to invite game.  Typically the simple major raise covers a spread of 3 or 4 hcp, and opener is unsure about game.

This is done only with the majors, as usually a new suit after minors shows stops for NT purposes.  Bidding 3 of the major is the simplest trial bid, and this is fine if responder is minimum or maximum, but what does he do if he is in between?  This is where most people make a trial bid in a suit.  With a minimum, responder signs off in three, with a maximum he bids game, and in the middle makes a judgement as to whether his holding in that trial suit in an asset or otherwise.

Some people play "long suit with values" trial bids, eg KJx.  Others play "long suit with nothing" trial bids, eg xxx.  Yet others play "shortage" trial bids, such as x.

This information is a godsend to the opponents who are wondering what to lead!  "Values" trial? - Can't lead that suit, it will either give tricks away or give a free finesse where the timing may not be there for declarer to do it himself.  "Nothing" trial bids? - a clear-cut lead.  You are safely leading through dummy to whatever partner holds.

Why help opponents?  A third of the time responder is going to sign off in 3 regardless of your trial suit, a third of the time he will bid game regardless of your suit, and only on one third of the time will it help reach the right contract.  But at what great expense!  What you really should do is not show anything at all two thirds of the time, and only when it makes a difference show something that will NOT significantly help defence.  Tricky.

The answer is to have a new trial bid.

This trial bid is the next step in the bidding :  1♠ 2♠ 2NT,  or   1♥ 2♥ 2♠. The bid means nothing other than that it invites game.  Responder bids game if maximum, signs off in 3 if minimum, and in between he bids a "no values" suit.  Something like xx or xxx is ideal.  This is the least helpful information to the defence's lead, and it assists opener to make the decision whether to bid game.

A minimum responder signs off in trumps.  A maxiumum responder bids game.  An in-between responder bids ...

After 1♠ 2♠ 2NT
    3♣ is a nothing club suit
    3♦ is a nothing diamond suit
    3♥ is a nothing heart suit.

After 1♥ 2♥ 2♠
    2NT is a nothing spade suit
    3♣ is a nothing club suit
    3♦ is a nothing diamond suit.

The reason 2♠ has to be the trial bid with hearts as trumps is to allow room to show a nothing spade suit.

However, this DOES NOT STOP opener using any other non-jump bid as an old-fashioned trial bid, provided there is something specific he wants to know.  By partnership agreement, this could be 3 cards with one of the top 3 honours, or a no-values shortage, but it needs to be an exact question that is asked.  If opener bids the next step over trump agreement,  this is the general "don't give away any information" trial,  while any other bid asks that question about a specific suit.  After spade trump agreement, any suit is the specific suit ask.  After heart agreement, 2NT would substitute for the ask in spades.

Why not try a more modern trial bidding method, and stop making life easy for the defender on lead?

In summary,  after 1M 2M,     2(M+1) is the game invitation bid.

Ray Green (fromagegb at gmail.com)        revised Feb 2016

Transfer Walsh - the basics    (Detail below)

Feb 2016

Transfer Walsh is a method of continuation after a 1♣ open in a normal system, eg Acol with 5 card majors, or two over one, but not a strong club system.
Why have something new?  Consider some of the deficiencies of standard natural methods ...

You have a biddable but weak hand with 5 hearts.  Can you show that your suit is 5 cards and weak?  Or can you miss the 5/3 fit, or avoid a 5/1 fit?  If opener always raises on a 3 card suit, then you are in trouble when you have only a 4 card suit.  (Other simpler methods such as a major response that guarantees 5 cards can solve this particular problem, but have other deficiencies.)

You as responder have a weak hand with 5 spades and 4 hearts.  Can you show the lengths in both suits, and the weakness, and play in the best fitting 2M contract opposite a balanced minimum opener?

This time you have 6 spades.  Can you show precisely that length, at all strengths?

You find your major fit, but to invite game you bid 3M which opener passes.  You have your combined 24 points, but on a bad break or losing finesses, you go one off.  Wouldn't it be nice to use 2M as a game invitation, so that a weaker opener can play there?

OK, enough.

Transfer Walsh enables you to show, precisely, whether your majors are 4, 5, or 6 in length,  and ALSO, whether you are weak, invitational, or game forcing.  This is for all combinations, and for one or both majors.  With the treatment described below, all game invitational responder hands are shown by a bid at the 2-level, opener knowing whether it is 4, 5, or 6, and if the invitation is declined you play at the 2-level.
It is completely EBU legal at level 3 or higher.

You can play it with a weak 1NT or a strong 1NT.   My preference is 1NT=15/16, and this article reflects that, but if yours is different, you can alter the rebid strengths accordingly.  My 1C open if balanced is 12-14, or 17+.

Transfer Walsh at its basic level is simply a reply of 1♦ to show hearts, and 1♥ to show spades.  The suit could be 4 cards or longer.  This is NOT a transfer per se, as opener does not necessarily complete the transfer.  There are many treatments and variations, but probably the key decision is what constitutes a transfer completion at the one level.  There are essentially two alternatives when you do not have 4 card support - complete the transfer with 3 card support and break it by bidding 1NT with 2, ignoring strength;  or complete the transfer with lower range strength (eg 12-14) and break it by bidding 1NT and higher strength (eg 17/18), ignoring whether 2 or 3.  Having tried both strains, my preference is the latter.  When responder is weak, playing in a 5-2 major fit at 1♥/♠ is better than playing in 1NT or higher.

These are the typical opener rebids after a major "transfer" :
    If you have 2 or 3 card support and a 12-14 count, you complete the transfer at the 1-level.  Responder if less than invitational strength passes with a 5 card suit, but with only 4 bids 1NT, or tries spades over hearts.  Responder with stronger hands makes further moves.
    If you have 2 or 3 card support but a 17/18 count, rebid 1NT (or 2NT with 19+).
    If you have 4 card support, you jump to 2 of the suit with 12-14, or 3 of the suit with 17/18.
    However, if you do not have 3 card major support, a rebid of 2♣ shows 6 clubs.  (The 1♣ open is usually balanced, but can alternatively be a long suit.)
    When you have 6 clubs and also 3 card major support, and responder with only 4 of the major rebids 1NT after your major completion, you of course convert that to 2♣.

That's it in outline.  If opener shows a 17/18 hand with 1NT, responder can transfer to show a 5 card suit.  Opener will play in 2M with 3 card support, but with only 2 cards will rebid 2NT - the combined minimum count makes this safe.  Whatever opener does, responder can of course raise to game now.

As responder with spades will bid 1♥, the initial response of 1♠ is now freed to have other meanings.  If you use this as a relay, or to transfer to 1NT, this has advantages, as it both right-sides a NT contract, and enables you to have follow-on bids if you wish.  Doing this then of course frees up a 1NT response to mean something else.  You can use that 1NT, or the 1♠ bid if you want a natural 1NT, to show a diamond suit in a weak hand, that allows partner to pass/raise or correct to 2♦.  However, there may be better uses ...

That is the basic essence of transfer walsh.  Over opener's rebid you can play any method of your choice, such as xyz, transfers, or whatever.
Discuss objectives, style, and continuations with your favourite partner.  To give an idea of more complex methods that you might use, I present below the key points in the approach I use.

An example transfer walsh system that utilises more complex developments

Objectives :
    Convey immediately whether opener is balanced or has long clubs
    Convey balanced opener strength ranges (12-14, 17/18, 19/20)
    Convey responder strength ranges opposite a 12-14 (up to 10, 11/12, 13+)
    Show precise lengths of responder's major holdings within those ranges.
    Allow responder to describe minor suit holdings in those ranges, but without exact length definition
    Where possible to right-side the contracts so they are played by opener
    Where possible to express a game invitation such that if there is a major fit, but no game, it can be played in 2M
    Enable a weak responder to show a 4 card major, but if no fit is found, to play in 2♣ or 2♦
    Cater for interference from opposition

Key treatments adopted :

1♣ may be 6 card, or is balanced and guarantees at least a doubleton in each major.  The balanced hands include a 20 count, so a 2NT open is therefore 21/22, and 2♣ then 2NT is 23/24.

The initial responses to 1♣ are:
    1♦ shows hearts, at least 4 cards
    1♥ shows spades, at least 4 cards
    1♠ is a relay denying a 4 card major.  Responder may be balanced, or have a long minor.  This frees the 1NT, 2♣, 2♦ replies.
    1NT shows {54} in the majors (either way)
    2♣ is {44} both majors 11+
    2♦ is {55} both majors
    2♥/♠ is natural 6 card, up to 8 hcp
    2NT is {55} in the minors
    3♣/♦ is natural, weak and preemptive

Apart from a weak {44}, "both major" responder hands show both suits immediately in one bid.  This means that in competition both suits are precisely known immediately, and X is unambiguously for penalty.

Opener to a "1red" response with 4 card support completes the transfer with a jump.  With 2 or 3 card support he completes the transfer with 12-14, rebids 1NT with 17/18, 2NT with 19/20.  Over the NT rebids, stayman, minor suit stayman, and 4 suit transfers apply (normal responses to NT are on).  Opener rebids clubs with a 6 card suit, but with 3 card support he initially completes but then converts a possible NT to clubs.

Responder on transfer completion can pass if weak with 5 cards,  or "retransfer" to show 5 and invitational or better 11+.  Opener will decline the invitation by rebidding NT on a doubleton, or the major with 3, (but responder can raise to game, or ace ask etc),  or accept by bidding game.  A fit declined is played in 2M.
A 6 card responder shows 9-12 by raising the major, and 3M from opener therefore invites the 11/12 to bid game.  Responder with 13 just bids game.
A responder with a non-fit 4 card major can rebid 1NT or 2 of either minor to play, except that after a heart transfer, a spade/NT inversion is used so that opener plays 1NT in the sequence 1♣ 1♦ 1♥ 1♠ 1NT, and opener plays spades in the sequence 1♣ 1♦ 1♥ 1NT 2♠.  After the inverted 1♠, responder with 4 hearts can then also make a game invitation in a long minor as below.

Opener to a "1♠" relay rebids clubs with 6, else bids 1NT 12-14, 2NT 17/18, and with 19/20 bids 2♥ to puppet 2♠ then rebids 2NT.  (If he rebids 3♣ over 2♠, this shows a natural heart reverse.)
"NT continuations" are off, because a minor is to play, and a major bid by responder (having already denied the major) is a slam invitation in the corresponding minor.

Responder after 1♣ 1♠ 1NT can pass or raise if balanced (eg 2NT on 11/12), bid 2♣ or 2♦ to play, bid 3♣ or 3♦ as GF, or bid 2M (having already denied the major) as a game invitation in the corresponding minor.  This latter can be played in 2NT or 3m if opener refuses the game, depending on fit.

The "both majors" nature of some of the responses makes it easy to show both the hand strength and major length after 2nd seat opponent interferes with a 1-level bid.  It is "system on", with X meaning "I would have bid that", so 1♣ (1♠) X is balanced or a minor.  Higher bids are as uninterrupted.  If the opponent bids a major, then the "both majors" meaning applies now only to the other major, so after 1♣ (1♥) responder shows his spade holding by :
    X = 4 spades exactly, up to 10 hcp
    1NT = 5 spades exactly, up to 10 hcp
    2♣ = 4 spades exactly, 11+
    2♦ = 5+ spades, 11+
    2♥ (cue) = 6 spades, 9/10
    2♠ = 6 spades, up to 8

Discuss methods with your partner to design your own transfer walsh continuations, but I hope this gives you some ideas.  If you would like a copy of my detailed system notes, please email me.

Try it.       You'll have fun, and find it indispensible.

Ray Green (fromagegb at gmail.com)        revised Feb 2016

Green aces - introduction    (Summary at the end)

Feb 2016

This ace and king asking method employs the useful space principle where the ace asking bid is one suit (step) up from the 4 of the trump suit.  There are no ambiguous and unresolvable compressed responses, where in some circumstances such as extreme distribution or opposition pre-emption , you do not know whether a compressed reply is 3 or 0 aces, for example.  No compression is needed when you always have the same room for responses regardless of the trump suit.

4T+1 is the ace asking bid         (eg 4NT in spades, or 4♥ in diamonds).

This means partnership discussion is needed if the trump suit has not been agreed explicitly.  A few rules are :
    1) If a suit has been agreed, 4T+1 is always ace asking, even if this is a previously bid suit.
    2) A jump to one higher than 4 of a naturally bid suit is always ace asking : if you intended it to play, bid something else first – perhaps 4th suit forcing - and then bid that suit.
eg 1♥ 2♦(game forcing) stop 4♥ = ace ask in diamonds, whereas 1♥ 2♦(game forcing) 2NT 3♠ 4♥ = to play, because if opener wanted to agree diamonds and ace ask he could and should have done so a round earlier.

The responses to the ace ask are based on 5 aces, with the king of trumps counting as the 5th ace.  The “absolutely nothing” response (no aces, no Q of trumps) is the sign off reply of 5T.  Otherwise, replies are essentially in steps 1,2,3 for 1,2,3 aces (you can count on your fingers) :
    1 step = 1 ace … but see below
    2 steps = 2 aces
    3 steps = 3 aces … but see below
    4 steps = 5 of the trump suit = zilch, 0 aces
    5+ steps = higher than 5T = 4 aces, and shows the kings as would be shown to a king ask.

If you have 4 aces, you immediately jump in reply to the ace ask, to actually give your king response.  Asker would not be asking unless he was going on to ask for kings if you had 4 aces.  He will have an ace himself.

(PARTNERSHIP DISCUSSION - if you might want to ace ask with no aces yourself, you can agree to use a 0/5 compression, so 5 is bid as 0.)

The steps 1,2,3 need modification to discover the presence or absence of the Q of trumps.

The responses in full are :
    1 step = 1+/-Q   or   0+Q   or   3-Q
    2 steps = 2+/-Q
    3 steps = 3+Q
    4 steps = trumps = zilch = 0-Q
    higher = 4 aces and this is the K response.

(“3+Q” => 3 aces with the Q,     “0-Q” => no aces, no Q,     “2+/-Q” => 2 aces and perhaps Q.)

Discovering what the step 1 means

You have asked for aces and the reply is the first step.

You may be interested if partner has 3 aces (you have 1 or 2 yourself) but then you would not be interested in 1 ace.  You may be interested in 1 ace (you have 3 or 4 yourself).  You can never be interested in both scenarios, so your asking bid specifies which you are asking for.

Let's put this into real suit bids to make it clearer.  Spades are trumps.  4NT = ace ask.  The reply is 5♣ = step 1 (0+Q,  1+/-Q,  or 3-Q)
    5♦ = first step = “I am interested in the 1 ace scenario”  “do you have 1 ace?”
        5♥ = 1-Q  “yes, but no Q”
        5♠ = trumps = 0+Q  “no”  (trump sign-off = weakest bid possible)
        6♣ and higher = 1+Q  and this is my K response.
    OR
    5♥ = second step = “I am interested in the 3 ace scenario”   “do you have 3 aces?”
        5♠ = trumps = “no”
        6♣ and higher = “yes” 3 aces,  and this is my K response

Note that asker will be going on to at least small slam if teller has the aces asked for, so if teller has those aces he goes on to give his king reply as if asked with 5T+1.

Checking for the Q on the 2 ace response

Let's have clubs as trumps this time.  4♦ = ace ask.  Reply is 4♠ = 2 steps = 2+/-Q
    4NT = next step “have you the Q?”
        5♣ = trumps = no, sorry (trump sign-off)
        5♥ and higher = yes, I do have the Q, and this is my K response.

Teller with the wanted answer again gives his K response.  You will not ask for the Q unless you were going on to ask for Ks if partner had the Q.

King asking

As 4 of the asking suit (4T+1) asks for aces, the same suit (5T+1) asks for kings.
Because asking for kings commits you to at least a small slam, you will never ask for kings if there is an ace missing.   If you want to bid a small slam, just bid it : asking for kings will not help.

Similarly you will normally not ask for kings if the Q of trumps is missing.  If capturing the Q is on a finesse, then it is not good to be in a grand slam on a 50% chance; it is better to stay in 6.  However, if you know you have 10 card fit, then there is a good chance the Q will drop, or if one hand shows void of trumps, the other may be finessed, so here the Q can be ignored.

There are only 3 kings, as the king of trumps was counted as an ace.  When discovering kings, often it is important to find out about a specific king (or kings), and not the number of kings.  The responses to the king ask are therefore specific kings :
    0 kings = sign off in 6 trumps
    3 kings = bid 7 trumps
    1 or 2 kings, bid your cheaper king suit.

After 1 king has been shown asker can then bid another suit to ask if you have that one as well.  The reply to this is 6 trumps as a denial, or 7 trumps as confirming that you have that second king.

Example : spade as trumps
5NT = king ask
    6♦ = king of diamonds   (denies king of clubs, may still have king of hearts)
        6♥ = have this one as well?
            6♠ = no
            7♠ = yes, both diamonds and hearts

If asker needed the king of clubs, he would not have asked further but would bid 6♠.

When spades is not the trump suit, the king asking bid will actually be a suit (rather than NT), and here you show this particular king of the asking suit by bidding NT.

Example : diamonds as trumps
5♥ = king ask
    5NT = king of hearts ( Hearts is the asking suit, so 5NT shows ♥K.)    ( 5♠ would show ♠K, therefore this denies spades.)
        6♣ = have this one as well?
            6♦ = no.

Note that here the king of hearts is a cheaper response than showing the king of clubs, even though hearts is higher ranking, because the asking suit king is shown by bidding NT.

In the same way, after 1 king is shown, asker can bid 5NT to ask for the king of the asking suit.

Example : diamonds as trumps again
5♥ = king ask
    5♠ = only, or cheaper king (may still have a second)
5NT = have hearts as well?
    7♦ = yes, I have ♥K and ♠K.  (Teller, with both, worked out that spades was cheaper to bid than hearts.)

In that last example, asker was not interested in the club king (he either has it or doesn't need it).
He may not have been interested in the spades, either, as hearts might have been all he needed to know.

Bypassing the King ask

If asker, on receiving the ace reply, bypasses the king ask by bidding higher than 5T+1, he is asking about the specific suit he is bidding.  He is not interested in kings, but wants to know your holding in that suit :  maybe he has the king and wants to know if you have the queen which will set up his long side suit.

The responses to the specific suit ask ("SSA") need to be discussed by the partnership, but the common reply is that signing off in 6T (you are already committed to the small slam) denies the queen, whereas bidding the grand slam shows it.  This is all there is room for if the suit asked about is the one below trumps, but if there is more room (eg the suit is two below trumps) then more things can be shown.  You could agree that  step1 = just Q,  step2 (6T) = just K or nothing,  7T = both K and Q.
The 6T signoff includes the K alone, as if that was what partner wanted to know, he could have asked for kings as normal.  Adopting this reply can find the grand whether partner was looking merely for the Q or actually looking for both the K and the Q.

OPPOSTION INTERFERENCE

If they bid one or 2 steps over the ace asking bid, there is no loss of information.  “Pass” = “I would have bid beneath that bid”, and “X” = “I was going to bid that.  Higher bids are as normal.
eg 2-step interference,  “pass” = 0+Q,  1+/-Q,  or 3-Q,  and asker then goes “X” = “I would have bid that” meaning “I am interested in the 1-ace scenario”,  or  “next step” = “I am interested in the 3-ace scenario”.

If they bid 3 steps over the ace asking bid (ie the suit beneath your trumps) then you do not lose any ace definition, but you do lose the ability to show the Q.
    Pass = 0 or 3   (to be resolved, don't worry!)
    X = 1
    5T = 2
    >5T = the normal response with 4
After “Pass”, X asks “is it 0 or 3?”  with the replies of 5T = 0, king response = 3.

Similarly if next opponent bids over an ace response, asker has the same method of continuation :
    Pass = I would have bid less than that, eg. the 1-ace scenario ask
    X = “I would have bid that”, eg. the 1-ace scenario ask, or the 2-ace scenario ask, or the Q ask
    Higher bids are as normal.

The same principle applies to interference over a K reply.

Green aces - summary

Ace ask = 4T+1

        step1 =  1+/-Q  or  0+Q  or  3-Q

                first step = “interested in the 1 ace scenario”

                        step1 = 1-Q
                        step2 = 5T = no ace
                         >5T = 1+Q and this is the K response

                second step = “interested in the 3 ace scenario”

                        step1 = 5T = no
                        >5T = yes, 3 aces, and this is the K response

        step2 = 2+/-Q

                first step = “have you the Q?”

                        step1 = 5T = no
                         >5T = yes, and this is the K response

        step3 = 3+Q

        step4 = 5T = zilch, = 0-Q

King ask = 5T+1

        6T = 0 kings
        7T = 3 kings
        other = that K, or the cheaper of 2 Ks    (NT substitutes for the K of the asking suit)

                new suit = “do you have this one as well?”

                        6T = no
                        7T = yes

Ray Green (fromagegb at gmail.com)        revised Feb 2016

Feb 2016

What strength should a 1NT open be?  Do you really need it?  Comparing sequences that start with 1♣ with sequences that start with 1NT, you find that there is nothing you can show after 1NT that you can't show after 1♣, and indeed the 1♣ gives more fit-finding options at a lower level.  So maybe you don't need a 1NT open?

To answer this, I thought it would be worthwhile to start from first principles to work out the logical strength for NT openings or rebids.  In this analysis, I am assuming typical flat hands, ignoring long suits that run for more tricks.  Of course you have to use judgement to vary the numbers depending on the hand.

There are different ways to bid NT.  You can open 1NT,  open 1 of a suit and rebid 1NT,  open 2NT, open 1 of a suit and rebid 2NT.  Without any preconceptions, what are the most efficient ranges for these?  To make 3NT with balanced flat hands you would expect to have 25 points, to make 2NT 22.5 points, to make 1NT 20 points. (Either side can typically make 1NT with 20, the advantage being with declarer.)

An obvious point to note is that there is room for game inquiry over a 1NT open or rebid, but no room over a 2NT open or rebid.  Responder here bids game or passes.  For this reason the opener range for a 2NT bid must be minimal, and 2 points is practical and realistic (like the Benjamin 2NT bids).

A starting point has to be "what strength is a minimum open?"  This analysis adopts the common agreement of 12 points to open.  The NT ranges would be different if it was not 12.  If an opening is 12 points, for "safety" responder needs 8 to reply, but 6 is better because going 1 off is often better than the opposition making their 2-level contract.  Take 6 hcp as the minimum reply.  Again, this is the standard.

As we could have the lowest range of NT shown by 1♣(say) then 1NT, and a higher range by a 1NT open, or the other way round,  let's start by looking at the next higher range which is 1♣ followed by 2NT.  How strong should this be?  Responder will bid with 6 hcp, and to make this useable for 2NT, opener must have minimum of 17 hcp.  A 2-point range therefore means 1♣ followed by 2NT is 17/18.

This means 12-16 needs to be covered by our two lowest ranges.  Splitting this into a 3-point range and a 2-point range, this again can be either way round.  The 3-point range will need an invitation, but a 2-point range does not really need one :  is the presence or absence of a Jack in a random suit going to make a significant difference?  Not really; with a 2-point range you can just decide on game or not.  Alternatively, the whole 12-16 may be covered by just a suit open and a 1NT rebid, but how wide can a range be to have effective invitations?  Responder will invite if a combined 25 hcp is possible, but should not do so unless there will be a minimum of 23, as you must be able to play in 2NT.  This means a 3-point range for opener is needed for an effective invitation.  We therefore do need two bids for this range.

( Note therefore that the Acol wide-ranging 1NT rebid of 12-16 is wrong.  If opener can have 16, responder has to make a forward move beyond 1NT with 9, and if opener has only 12 then you are playing 2NT with a combined 21 count.  Very bad indeed!  Moreover, if opener then bids game with 15, you are playing 3NT on a flat 24 count.  This is often wrong, too.  So let's try responder making a forward move with 10 points, and passing with 9.  Now the 2NT contract is better, but still a risky 22.  And you are now missing 25 point 3NT games.  Who invented this silly idea?)

This answers one of the initial questions -  you do need a 1NT open.

If the 1NT open has a 3-point range -  what range is best?

If you open 1NT and partner has a hand that can bid or invite game, then you have no problem.  Everybody has methods for this.  The problem comes when partner has a weaker hand, so has to pass.  With a weak hand you cannot determine the best contract and stay below 2NT.

Yes, the 1NT open is pre-emptive, but when you open 1NT you already expect the hand to be yours rather than the opponents (statistically your side has more points than theirs), and you are pre-empting partner more than you are pre-empting the other side.  For this reason, you want partner to have at least an invitational hand the majority of the time.  Let's look at this with regard to the strength needed to open 1NT.

If you have an average of a 13 count [Acol 12-14], partner is statistically expected to have 9 points, so 11+ for a game invitation is comparatively rare.  This is a waste, as all he is going to do 70% of the time is pass or make a guesswork takeout.  You don't find your major fits.  Compared with people who are playing a strong NT on these hands,  you will see on the travellers that your 1NT tick scores badly against their 2♥ tick.

If you have an average of 16 [standard strong NT 15-17], partner typically has 8 hcp, so he is already at the invitational level.  You can use Stayman.  More than half the time you will have a sensible auction.

As is apparent, a weak NT is waste of space in a constructional sense, and as the opening range gets stronger the better it is.  When constructing a system, this has an influence.  1NT should be strong.

Our 12-16 range that needs covering could therefore be split as 12/13 opening 1♣ and rebidding 1NT, with a 1NT open of 14-16.

How about a 1NT open with a 2-point range?

This is better still, as you do not need an invitation.  Responder can use Stayman and rebid 2NT to play, and the immediate response of 2NT is freed to have some other use.  This is more effective, so our 12-16 coverage is best covered by 12-14 opening 1♣ and rebidding 1NT, while a 1NT open is 15/16.

Ranges higher than a 2NT rebid?

We found above that a 2NT rebid should be 17/18.  If you can have a 3NT rebid (see below, but assume you can find a sensible method for this) how strong should it be?  As responder will pass with 5 hcp, opener must be a maximum 19 when opening 1♣ to avoid missing the 25 point game.  As responder can be 6, opener rebidding 3NT must be a minimum of 19 to have that 25.  So 1♣ then 3NT = 19 exactly.

This makes the 2NT open = 20/21.  This is NOT guaranteed safe, as responder may have nothing.  But a few points may enable it to make, and the chances are partner has something, even your normal partner.

Above 21 there are various methods.  The Benjamin style gives two different ways of rebidding 2NT after a 2-open, and Kokish after a 2♣ open can achieve this.  These can show 22/23, and 24/25.

Summary of all bids

    1♣ then 1NT = 12-14.  Responder needs 11/12 to invite, but fits can be explored at the 1-level.
    1NT = 15-16.  No invitation needed.
    1♣ then 2NT = 17/18
    1♣ then 3NT * = 19
    2NT = 20/21
    Higher ranges beneath 3NT split into 2-point ranges according to method chosen

* Jumping to 3NT is not usually a good idea, as it misses the oportunity to find fits when responder has additional length in one suit, or is 2-suited, so your methods will normally have some forcing bid, followed by a possible 3NT rebid.

Compare this NT ladder with standard bidding (ie in the rest of the world, not Acol)

Very close, perhaps not surprisingly.
Standard has 1NT open = 15-17, and 1NT rebid = 12-14.  Now 1♣ followed by 2NT would be 18-19, and no special forcing method is therefore needed to show 19.
Simple and practical.

Compare this NT ladder with classical Acol (1NT open = 12-14 and rebid is 15/16)

The openings of 1NT, and 1♣ then rebid 1NT, are reversed.  That's a matter of choice, Acol's choice now being poor, as opening 1♣ on weaker hands gives much better fit finding as shown above.

Compare this with alternative Acol (1NT rebid is a wide-ranging 12-16)

That extended range can push you into a failing 2NT if opener is minimum and responder is minimum for the invitation, or can lead to missed games, as explained above.
Poor, but compared with classical Acol this has the advantage of being able to open 1♣ rather than 1NT.

Handling the 19 count

This can be awkward.  Standard 1NT = 15-17 avoids the problem.  The normal way is to make a forcing rebid then follow with 3NT.  Some people play 2NT = 19/20, but this is ineffective as responder needs to be stronger to be able to look for a fit.  It is bad when responder is very weak.  Also with a 19 count you are not going to miss game by opening at the 1-level if responder is bidding on 6 hcp.

Alternatively, if you are playing 5 card majors, transfer walsh enables you to have two ways of rebidding 2NT which therefore can show 17/18 and 19/20.  This is the best option as it shifts the remainder of the NT ladder up,  so a 2NT open = 21/22, while 2♣ then 2NT is 23/24, and 2♣ then 3NT is 25+, keeping 2-point ranges all the way and avoiding the restrictions imposed by Kokish methods.

Non-balanced hands

Of course in the right range you open 1NT on 2335, 2344 and 3334 shapes, but what about 2245 or singletons?  If these are "forbidden" by style then you will probably open 1 something and rebid 1NT if responder plugs one of your gaps.  This means you suffer the same problems of the wide ranging 1NT rebid : ergo you may decide one or both of these should be opened 1NT, or maybe only use a 1NT open for a 2245 without a 4 card major.

Ray Green (fromagegb at gmail.com)        revised Feb 2016

Feb 2016

Assuming your choice of system is natural with 5 card majors, you then have to consider the other one-level openings.  Having decided on using transfer Walsh responses to a 1♣ open, because of the benefits they bring, you need to adopt a NT strength range that is appropriate and all you are left with is the 1♦ open.  I would like to suggest that it is not simply a matter of choosing between "4 card diamonds and a possibly short club" and "better minor but clubs if 3/3 and diamonds if 4/4", as there is more to it than that.

Consider whether you really need to show a 4 or 5 card diamond suit.  I am sure the majority would open a hand within their no trump strength range and a shape 3253 (spades first) with a bid of 1NT, and not think twice about it.  They eschew showing a 5 card diamond suit in favour of the 1NT.  This is sensible, as pairs scoring favours the majors and NT over the minors - if a diamond contract makes one more trick than the NT contract, then NT is preferred.   Now think that if the 1♣ open is better than the 1NT open as it enables you to find both NT and major contracts, then maybe you should open 1♣ on this hand ?

Follow the thought train, and you'll find that hidden, completely unexpected, benefits emerge.  Let us say that we will open 1♣ with any balanced hand, or semi-balanced hand, but not a hand with a singleton.  (A 2452 shape is semi-balanced.)  However, we like the benefits of our 5 card major methods, so will only do this with a 5 card minor.   A six card suit falls outside this; we will say that we will always open and rebid a 6 card suit.   This means that a hand with a singleton or void will open 1♦.  Unfortunately, this may not work out well if the void is in diamonds, so we will say that that hand has to open 1♣.  The definition of a 1♦ open is therefore either a 6 card suit, or a hand with a singleton or void outside diamonds.

Our opening structure then becomes these bids in descending order of selection.  For each hand you pick up, you go through this list from the top down and make the first call that fits the criteria.  You have the values for a 1 level opening.

    Open a 5+ card major.
    Open and rebid a 6 card minor.
    Open 1NT if the right shape and range.
    Open 1♦ with any singleton or void except diamonds.
    Open 1♣ otherwise.

You will note that this throws more hands into the ambit of the 1♣ open than would occur with other methods that would open 1♦.  But this is exactly what we want; we like the transfer Walsh enabled methods that follow.

The opening selection method also benefits the 1♣ open, as unless you rebid clubs to show 6, it now guarantees at least a doubleton in each major.  This ensures a 6 card major in responder's hand makes a good contract.  Without a fit, the lack of a shortage ensures an eventual NT is not unreasonable.

This method also has hidden benefits in the 1♦ open.  The 1♦ open is either essentially 2 suited in the minors, or is single-suited in diamonds, or is 3 suited. With absolutely natural responses, after a start of say 1♦ 1♠, opener with no fit will rebid 2♣ with the 2 suited minor hand, rebid 2♦ with a 6 card suit (responder knows this is now 6, not merely 5), or with a shortage in responder's suit bid a natural 1NT (or 2NT depending on strength). Over the NT responder now knows it is a waste of time rebidding his 5 or 6 card suit.  That alone can avoid unmakeable contracts.  As the opener is known to be 3-suited, responder can safely bid any of the other suits to play.

You might ask "what if opener's hand is not one of these 3 types?".  Well, it has to be one of those 3.  Opener has at most 5 diamonds.  Opener has a singleton or void in clubs or a major.  That leaves 8 cards or so in the other two suits, without 5 in a major, and therefore a fit in responder's second suit is guaranteed.  After 1♦ 1♠ 1NT, responder with a weak hand and 4 hearts can safely bid 2♥ for example.  Opener will be 0445, 1444, 1435 etc.

Opener will support a major if he has 4 of them, of course, but he will also support a major where he has 3 card support and a side suit shortage.  1♦ 1♠ 2♠ could be bid on many hands that have 4 card support, but the worst case is a 3154 shape.  Should it turn out to be a 4/3 major fit, you expect this to be playable because there are ruffs in the short suit, and, moreover, the ruffs are made in the hand with 3 trumps.  3154 is the absolute worst case, because one fewer heart would mean an extra spade, an extra diamond would cause a rebid of 2♦, and an extra club would cause a rebid of 2♣.  One fewer minor would of course mean an extra spade.  One more heart, on the other hand, making the 4/3 fit a poor bid, would mean that the hand no longer falls in the 1♦ opening category, and it would be opened 1♣.

However, note that if opener is 4351 and the bidding starts 1♦ 1♥, opener will rebid 1♠ rather than support hearts.  This is because responder may be equal length in the majors.  Responder can bid diamonds or correct safely to 2♥ as he knows opener is 4351.  (Opener would rebid 1NT with short hearts.)

Playing the 1♦ open in this way means that over 90% of the time the opener will have 4 or more diamonds, so for diamond raises you should support with a 4 card suit - inverted raises or not according to taste.
 

An example unbalanced diamond treatment that utilises more complex developments

Playing the natural style, as above, if as responder you have and bid a major, opener with no major will show a single-suited or two-suited hand, and then it does not really matter what major you have.  If opener has a 3-suiter with only the other major, he will bid NT.  If you reply hearts you can find a spade fit, and if you reply spades you can find a heart fit.  
It does not matter which you show as you will find the fit! 

Consider what would happen if you replied 1♥ whichever major you had.  Opener with spades will bid 1♠ and now you can raise spades if that is your suit, or bid something else if your suit was hearts.  (Opener has described his hand as a 3-suiter short in hearts, so it is easy to pick the right contract.)  Opener with a 3-suiter without spades will bid 1NT and now if your suit was hearts you can bid 2♥ knowing you have a fit, and if your suit was spades, you pass 1NT or convert to a minor.

This means that you can reply 1♥ with either or both majors, and will always find the fit if there is one.  Hey! You now have a completely spare reply of 1♠!
You can use this as an artificial bid meaning "any hand, invitational or better",  while 1♥ means "either or both majors, but less than invitational".  Similarly any reply greater than 1♠ is known to be weak.

The use of the artificial invitational 1♠ allows opener with the 1-suiter or 2-suiter to decline or accept in his first rebid, making continuations (if any) simpler, and with the 3-suiter he always rebids 1NT.  Responder can then use 2♣ as a relay to find the short suit, and a major fit can be shown at the 2-level which is already known to be an invitation.  A declined major fit plays in 2M rather then 3M.  Alternatively, a game-forcing responder can then bid the short suit to set up a GF, and subsequent bidding has more space available to explore the correct contract and level.

Develop your own responses in your own style, or contact me if my system notes would be of interest, but however you play the unbalanced diamond you will find it pays dividends.

Ray Green (fromagegb at gmail.com)        revised Feb 2016

Used in agreed circumstances only, to define the odd/even lengths of all partner's suits suit in one hit, and therefore by a simple rule, also those of declarer.

Background and theory

“Parity” is defined as a suit length being either odd or even. Normal defensive methods commonly give partner your parity (“count”) in the suit being played, as this is often more use to him in defence than it is to declarer. Rather than just show the parity in one suit, prism signals show the parity in all suits in one go, and this can be of great help when a new suit is opened up before you have a normal count of that suit.

In a hand of 13 cards there will be 3 suits of the same parity, and the other suit will be of the other parity. That last suit is defined as the “prism suit”. The parity of this suit is defined as “prism parity”. The combination of the 2 defines the hand, so for example a shape of 5233 has a prism description of “even:hearts”. (Note the other 3 suits are odd parity). Similarly a 4333 is even:spades, and 4072 is odd:diamonds. A void is even parity.

Agreed circumstances and method

When the dummy goes down, work out and remember your own hand's prism description and also that of dummy. In the initial play you show your own hand type to partner while at the same time interpreting his description to you. How ? Often declarer will draw trumps when he gets in. When declarer does draw trumps, or if you lead trumps, both defenders show their prism parity and suit. This is the simplest circumstance.

If you have :

Zero trumps or One trump

The first discard shows the prism parity : an even discard is even prism parity, an odd discard is odd (the suit is ignored). The second discard shows the prism suit, in revolving style (eg if hearts are trumps, a high diamond shows spades, a low diamond shows clubs, a hi spade shows clubs, a low spade shows diamonds, a hi club shows diamonds, a lo club shows spades). Note that this discard shows the prism suit, it does NOT ask for a lead of that suit.

(You could alternatively use a McKenney/Lavinthal style to indicate the prism suit.)

Two trumps

Play hi-lo to show even prism parity, lo-hi to show odd prism parity. The first discard shows the prism suit, in revolving style. (If you followed hi-lo then your discard is meaningless, as your prism suit is obviously trumps.)

Three trumps or more

Play the first 2 cards hi-lo to show even prism parity, lo-hi to show odd prism parity. The third trump shows the prism suit. You have a choice of 3 cards to keep for the 3^rd round to show this : the highest card last shows the prism suit to be the highest ranking, spades (or hearts if spades are trumps); the lowest card last shows the lowest ranking, clubs; and the middle card of the 3 shows the middle ranking of the other 3 suits. For example, hearts are trumps, and you have 972 ...

972 (in that sequence) is even:clubs,      927 is even:diamonds,     729 is even:spades

279 is odd:spades,    297 is odd:diamonds,     792 is odd:clubs.

Four trumps

If you are odd prism parity, you show your hand completely in the first 3 cards. If you are even:trumps then you have had to lie in showing your prism suit, so if you can, show it to be one you have already shown as odd by length signal - maybe on the opening lead – as this might expose the lie. (If you are even:not-trumps then the signal is pure.)

What if you have a trump honour?

If you have a picture in trumps then play naturally – PRISM IS OFF. However, your first 2 of 3 can still often show the prism parity. Partner's play is not affected, so you can still work out his hand.

If declarer fails to draw 3 rounds of trumps (the boss trump may be left outstanding in one of the defenders' hands or there may be no more trumps out) then in the first 2 rounds you have already shown your prism parity. Simple prism then abandons the showing of the prism suit. This information is still useful, because once length is shown in one suit by normal count methods, this may also define the others.

Other circumstances Prism can be used

You may agree to play prism signals on the run of a long suit from dummy in NT.
If only 2 rounds of trumps are played, you could make your next card (following suit) show the prism suit.
Play your normal signals (eg current length) at other times and before a prism is shown fully.

Finding declarer's hand

If partner has shown you his prism description and you remember yours and dummy's, then this gives declarer's.
The 3 known hands each have a prism suit and a prism parity. Combine the parities to get the collective parity, so for example even-odd-odd gives a collective even.
The suits will be all the same suit, or will be 2 suits (a pair the same and another) or 3 different suits.

Declarer's prism suit

If the known hands are all the same prism suit, so will declarer's.
If the known hands have 2 suits, a pair and a single, declarer's will be the same as the single, so making 2 pairs.
If the known hands are in 3 suits, then declarer's will be the fourth suit.

In summary, the 4 hands will all have the same prism suit, or there will be 2 pairs, or they will be all different.

Declarer's prism parity

This will be the opposite of the collective parity, except it will be the same parity when the hands all have different prism suits.
For example, if the 3 known hands are odd:spades, even:hearts, even:spades, declarer will be even:hearts
This can be useful if, for example, he ends in dummy and leads way from a suit headed by the king and you know he is odd in that suit, and (by the bidding) comparatively short. You may go up with the ace to prevent him sneaking a trick with a singleton queen.

Take an example. The bidding by opponents goes 1♠ 2♠ 2NT(general trial bid) 3♠.
You have
    ♠ J
    ♥ Jxxx
    ♦ Axxxx
    ♣ xxx
When dummy goes down you see
    ♠ Qxx
    ♥ xxx
    ♦ Kxxx
    ♣ Kxx
You are even:hearts, dummy is even:diamonds.

Partner leads ♥ KAx and declarer follows with x, then the Q, then ruffs the third round. He draws trumps with AKQ, partner following 528, then leads ♦x from table. What do you play ?

Partner has shown even:hearts, so declarer is odd:diamonds. Declarer is therefore known to have had 6 spades, 2 hearts, and has therefore 5 cards in the minors. Specifically he has 1 or 3 diamonds. Declarer with long spades is more likely to be short in diamonds than partner, so you play ♦A immediately, felling declarer's Q.

Declarer had
    ♠ AKxxxx
    ♥ Qx
    ♦ Q
    ♣ Axxx
and makes an overtrick if you don't go up with the ace of diamonds.
The prism signal enables you to find the correct defence.

Conversely, if dummy was the same but declarer had ♦ Qx, ♣ Axx and you went up with the ace, you lose a trick because declarer can then throw a losing club on dummy's ♦ K. With this hand you need to duck the first round of diamonds.
With this deal, partner would have shown odd:spades, so declarer is therefore odd:clubs. Therefore he has an even number of diamonds.
The prism signal enables you to find the correct defence.

Reliability, and is it worthwhile?

• If partner has a trump picture you are going to be misled, as for example he cannot signal the prism suit without perhaps losing a trick.
• If partner has 4 trumps and is even:trumps you may be misled.
• Opener may not draw trumps and the method cannot be applied.

Hands are rare that the method leads to an extra trick, as in the example above.