The same road, but harder to see
Alexis Carrel, a French surgeon and biologist who was awarded the Nobel Prize in Physiology or Medicine in 1912, said, “To accomplish our destiny it is not enough merely to guard prudently against road accidents. We must also cover before nightfall the distance assigned to each of us.”
The declarer and the defense know the distance assigned to each of them in a deal, and each hopes to cover that distance by nightfall -- trick 13. How can South finish the race first in today’s deal? He is in six spades, and West leads the diamond queen to dummy’s king. North gambled slightly by jumping to four no-trump, because South might have had two (or three) low clubs. But here it worked out.
South has two minor-suit losers and only 11 winners: six spades, three hearts and two diamonds. Since declarer needs to establish dummy’s fifth club, he must ruff three clubs in his hand. This requires four dummy entries -- three for the ruffs and one to reach the club queen. What are they?
Declarer immediately concedes that club trick. Suppose East wins and returns a diamond. South takes that trick on the board (entry one), ruffs a club high, plays a spade to dummy’s jack (entry two), ruffs a club (happy to see both opponents follow suit), leads a spade to dummy’s queen (entry three), and ruffs a third club.
Almost home, declarer draws West’s last trump, plays a heart to dummy’s queen (entry four), and discards his last diamond on the club queen (or, if he is a show-off, the club two!).