From the Middlesex Congress Swiss Teams in December.
At both tables the contract was one notrump played by South.
West led a small heart to the ace, a heart was returned to the jack and queen and West cleared the hearts.
At our table South played a spade to the ace in dummy and took the diamond finesse. Barry Myers sitting West gave this a smooth duck.
South now blithely assumed that the diamond finesse was working and cashed the top spades in dummy and finessed the diamond again.
Barry won and took the thirteenth heart and the jack of spades. South was in some trouble at this point since if she discarded two clubs the defence could probably take three club tricks, so she decided to discard her top diamonds*. Meanwhile East had discarded the nine of diamonds, so Barry was able to take two more diamond tricks and a club trick for a rather embarrassing two down.
In the other room Debbie Sandford demonstrated how it should be played. When she won the heart king she just played diamonds from hand guaranteeing seven tricks.
* In some variations the defence is able to play a stepping stone squeeze, those who are interested can work it out.