Many plays made by declarer are based on information obtained from either the opponents’ bidding or the type of defense they adopt. To place so much reliance on information volunteered by the enemy might seem odd, but it is nevertheless sound strategy to proceed on the assumption that they are always doing their best to achieve the optimal result for their side.

Consider this deal where South is in four spades doubled and the defense starts with three rounds of diamonds followed by three rounds of hearts. Declarer ruffs, cashes the ace of spades, plays a club to the king and leads a trump from dummy, East following low.

South must now resolve the question of whether to finesse or go up with the king. He is already down two — 500 points — and wants to avoid going for 800.

In general, when missing four to the queen of a suit, declarer plays for the queen to fall by cashing the A-K instead of taking a finesse. However, the mathematical advantage is so slight that he should feel free to make use of any and all clues that might indicate otherwise.

Here, there is a good reason to finesse. If South trusts the opponents’ bidding, he should assume that their spades are divided 3-1, not 2-2. In effect, he says to himself that the opponents would not have voluntarily bid four hearts if they each had two spades.

Of course, it is possible that they did — nobody bids perfectly all the time — but there is a strong presumption that they did not bid themselves into a hopeless game. From this it follows that the spades are unlikely to be divided 2-2, so that finessing against the queen is the better play under the circumstances.

Tomorrow >> Famous Hand.

— Steve Becker