THE PLAY'S THE THING
by Willie Zurfluh
THE PRINCIPLE OF RESTRICTED CHOICE
Every Bridge player has faced the following dilemma: you hold Axxx in your hand and K109xx in dummy, you lead the Ace and RHO drops the Queen or Jack. Do you play the King or finesse the ten? Most players think that it is a pure guess, but it is not. The odds are 2 to 1 in favor of the finesse. The stiff Queen or Jack are twice as likely as the doubleton Queen-Jack. If your RHO held the Queen-Jack he could play either one, but if he held a singleton his choice is restricted. That is where the name comes from.
The Principle of Restricted Choice comes up in other situations, as this hand from the 1958 Bermuda Bowl will illustrate. A low spade was led against 3 NT at both tables. At both tables the King was played and a low spade was returned. The American declarer played the Queen and went down one. The Italian declarer played the ten and made his contract.
Was this just a lucky guess? No! KJxxx or AJxxx are twice as likely as AKxxx. Once again the Principle of Restricted Choice comes into play.
3NT by South
One more example before I conclude this essay: You have Kxx in hand and AQ8x on the table. You lead low to the Queen and low back to the King. Your RHO plays the ten and the Jack. The finesse has an 88% chance of success. There are 8 combinations your RHO could hold and only one of them is Jack-ten-nine.BREWER BRIDGE HOME