Opening 1NT, Asptro

West must choose between showing his strength with a double and showing his major suits with a conventional bid.  This hand is about shape.  My instinct is to downgrade the singleton Jack and emphasise the shape.  2♣ shows exactly what he has - four hearts and another five-card suit.  East now has to choose.  The choice is between pass, 2♦ and 3♣.  West will usually not be quite this strong.  I must confess that I favour a pass.

Opening 1NT, Landy

Landy is a popular convention promising at least 5-4 or 4-5 in the majors.  On this deal East can do no more than ask for the longer major with 2♦, although pass, as above, is also possible.

Intermediate and above

Opening 1NT, transfer overcall

In this version of transfer overcalls the sequence shown promises at least four hearts and five spades.

Opening 1NT, double, basic wriggle

North’s pass is forcing as he initiates a ‘wriggle’ manoeuvre.  East is quite happy to defend 1NT doubled, and South redoubles as instructed.  West plays a waiting game, North bids his lowest four-card suit, and the spotlight falls on East.  Double is usually the winning choice, albeit with some risk attached.

Opening 1NT, double, Halmic

Playing Halmic North’s forcing pass followed by 2♣ promises 4-3-3-3 shape.

East will double to show his club holding, and will double again when NS eventually reach 2♦.

Opening 1NT, double, Helvic

Playing Helvic North’s 2♣ promises at least 4-4 in clubs and diamonds in principle, but with 4-3-3-3 shape responder bids the suit below the four-card suit as here.

Partner must bear in mind the possibility of three in the bid suit and four in the next higher suit.

East will double to show his club holding, and will double again when NS eventually reach 2♦.

Evaluation

Asptro is likely to lead to 2♣ played by West.  He should make about ten tricks.

EW will do well to make more than seven in no trumps, assuming that the defence does not set up the ♦Q as an entry to the clubs for them.

Both Landy and transfer overcalls lead to West declaring 2♠.  He will come to eight or nine tricks thanks to the division of the outstanding spades.  Nine tricks in spades will of course score better than ten tricks in clubs at pairs scoring.

And Cappelletti is all too likely to lead to a contract of 2♥ on a 4-2 fit.

An initial double, leads to NS playing in a doubled diamond contract, whatever the chosen version of a wriggle.  They will make four or five tricks.

Because of this, the initial double by West is by far the most effective action on this occasion, but East must find the subsequent penalty double.

Opening 1NT, Cappelletti

2♦ by W promises 5-4 or 4-5 in the majors.

East must choose a major, and he has a roughly 50% chance of getting it right.