East declined to cover dummy's jack as declarer led a club to the ace, cashed the ace of diamonds and ran the heart winners. South reduced to four spades but East was compelled to retain the king of diamonds and thus only three spades. West was forced to keep the king of clubs and three spades but South's four of spades won the thirteenth trick, N-S +1470. Declarer could simply have opted for a club finesse but a squeeze was very likely to materialize. At trick two, he runs the queen of clubs losing to the king but requires a squeeze for a twelfth winner when hearts break 4-1.
A 4-1 heart break would have culminated in a multi-trick set but the odds favored a 3-2 heart split. South could duck a heart but his trick total would be reduced to eleven. He would then require a club finesse or a squeeze for a twelfth trick.
At matchpoints, South's line of play was reasonable in search of an overtrick. At Imp scoring, he should advance and pass the queen of clubs to give himself the best chance of scoring twelve tricks.
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