What do you want to win

The chess player’s motto - “When you have found a good move, see if you can find a better one” is equally applicable to bridge. Here West’s defence was theoretically sound - he had made a clear signal to partner. But East, as partners can be, was blind or ignorant, and the contract was allowed to make. East’s fault? Yes - but only in part. West had an idiot-proof way to defeat the contract. Cover up East and South’s hand and see if you can find it. 

West led ♥A and East remembered to signal with ♥9 to encourage a continuation. West duly played ♥K and carefully led ♥8 to the third trick - a “suit-preference signal” for partner - after trumping - to return the higher ranking of the other suits - here ♦s. If West had wanted a ♣ return, he’d lead his lowest ♥ to the third trick. Such signals are most useful in trumping situations - but only if partner is aware of them. Evidently this East was not, for after much agonising and mental coin-tossing, East returned ♣3. Declarer gratefully won ♣A, led ♠A, and cashed dummy’s ♣KQ discarding ♦10. Contract made.

West criticised East for failing to obey the suit-preference signal, but West had an idiot-proof defence - he should simply have cashed ♦A before leading the third ♥ for East to trump.

ANDREW’S TIP: A victorious defence is better than a victorious post-mortem!