The fourth results in unusual play

Dr. Seuss claimed, “The main problem with writing in verse is, if your fourth line doesn’t come out right, you’ve got to throw four lines away and figure out a whole new way to attack the problem. So the mortality rate is terrific.”

In an uncontested bidding sequence, if the fourth bid is in the fourth suit to be named, it usually helps responder to solve his strain problem. Fourth-suit game-forcing announces that responder has an opening bid and is, usually, seeking a stopper in that fourth suit from partner.

Here South, with two solid heart stoppers, bids two no-trump, and North raises to game. After West leads the heart queen, what should declarer do?

South starts with seven top tricks: one spade, two hearts, two diamonds and two clubs. The other two tricks might come from either minor.

At first glance, it looks right to lose a diamond trick immediately. Then, when the suit divides 3-2, as it will 67.8% of the time according to the mathematicians, declarer will romp home with an overtrick. Instead, playing on clubs requires a 3-3 split, which is much less likely at 35.53%.

Here, though, the diamonds are not 3-2 and the clubs are 3-3 — how unlucky can South be?

If dummy did not have the spade ace, ducking a diamond would be right. But with that dummy entry, declarer can test both suits. He should start by cashing the top diamonds. If they are 3-2, he continues with a third round. But when they are 4-1, South switches to clubs. Overall, he has a 79.2% chance of success.