Better Play Hard

 Dlr: South ♠ K 7 5 4 Vul: N-S ♥ A Q 6 3 2 ♦ A ♣ K Q 2 ♠ A Q 3 2 ♥ — ♦ 7 6 4 2 ♣ A J 10 9 5
 West North East South 1♣ 2NT(1) Dbl 3♥ Pass Pass Dbl Pass 3♠ Pass 4NT Pass 5♠ Pass 6♠ All Pass

(1) 2NT = At least 5-5 in hearts and diamonds

Solution

As usual, declarer could count 11 tricks against any distribution and 12 if the trumps were an unlikely 3-2. After winning the first trick with dummy’s A, declarer played the ♠K and ♠A, getting the bad news that East had a trick in the suit. Declarer ruffed a diamond then cashed the ♣K. The ♣Q was overtaken with the ace. When West discarded a diamond, declarer paused to think. It was clear from the auction that East had longer hearts than diamonds. Otherwise, he would have bid 3 instead of 3. Declarer surmised that West began with 1=5=6=1 shape and East with 4=3=2=4 distribution. So, declarer cashed the ♠Q and played two more rounds of clubs, reducing everyone to four cards. Declarer now played his last club. East threw a heart because he saw that there was no point in ruffing. If he did ruff, he would have had to lead a heart, allowing declarer to take the last three tricks with two hearts and a trump. Discarding, however, that served only to delay his fate. Declarer now led a trump, throwing dummy’s remaining low heart. East got his trump trick but dummy’s A and Q took the last two tricks. If West had followed to the second club, he would have been marked with 1=5=5=2 shape, so a second diamond could then have been ruffed safely in dummy. The A would have taken care of declarer’s last diamond and all declarer would have lost would have been a trump trick.

The full deal:

 Dlr: South ♠ K 7 5 4 Vul: N-S ♥ A Q 6 3 2 ♦ A ♣ K Q 2 ♠ 10 ♠ J 9 8 6 ♥ K J 10 9 7 ♥ 8 5 4 ♦ K Q J 9 8 3 ♦ 10 5 ♣ 5 ♣ 8 7 4 3 ♠ A Q 3 2 ♥ — ♦ 7 6 4 2 ♣ A J 10 9 5