This was hand 2 from the session played at the Lansdowne on Tuesday 11th January. The par contract is 4♠  and this is how you get there. Landy is a defence tool that is particularly useful against a Weak NT. It guarantees 9 cards in the major. On this hand North has equal lenth in both majors so uses a relay of 2♦ to ask partner to name the 5 card suit. With 12 points North is well worth an invitation to 4♠  which North is happy to accept.

There are two instructive points in the play. Assuming West makes the natural lead of ♦ 10 East is going to very quickly reveal 8 points in diamonds and should east switch to the K♣ , 5 points in the club suit. Therefore, having advertised 12-14 points with the 1NT opening there is no room for East to hold the Q♠ . Thus South can confidently win the A♣ and play a spade to the 9♠ . As an aside East can make the great play of the Q♣ which may well lure South into taking the finesse into the West hand. 

Finally South has to be careful in the play of the hand. As you can see the break of the heart suit is 4-2 and relying on the hearts to break will result in the contract going one off. The way round this is to ruff three rounds of clubs. The effect of this is that trumps are drawn by North, known as the short hand.  This technique is known as dummy reversal. This is a play that is not easy to spot, but the two key requirements is a shortage of a side suit in the hand with longer trumps, and even more importantly top trumps in the short hand. In this case A109.

If you are playing outside the UK it is very rare to find anyone playing weak NT or more specifically 4 card majors. Here is a list that should be in your toolbox

Short Club or Better Minor
Wide ranging 1NT
Inverted Minor Suit Raises
Support Doubles
Checkback Stayman
Walsh Responses

 

Opening with 4441 Hands. Andrew Robson recommends the "Taps" approch

Luckily 4441 hands are quite rare — less than three per cent. But they are tricky, because you’ll have to break a rule.

There’s no perfect strategy for opening but a simple approach is “Taps” (H and C taps — only opening 1♥ or 1♣). With a black-suit singleton, open 1♥ ; with a red-suit singleton, open 1♣.

Very likely partner will respond in your singleton.  What then? With 13-14 points: rebid your cheapest four-
card suit.

With 15 or more points, rebid your cheapest four-card suit at the one-level; possible, rebid notrumps at the appropriate level to show your strength.

And 12-point 4441s? don’t open them.

Here is a video of the first in Andrew Robson's 4 week series in association of Real Bridge. A summary of the hands is as follows:-

1) Features or Ogust
2) When not to use 2NT
3) Bidding to the level of the fit
4) Opening on 7 card suits