A Double Strip

Can North/South make any game?

North/South cannot make 3 NT on heart leads. Does 5 ♣ or 5 ♦ make? No - there is no way for declarer to avoid losing a diamond, a heart, and a spade.

No, the only game which can make (double dummy) is 4 ♠.

Suppose West leads a heart. Declarer ducks the first heart, wins the second, and crosses with a diamond to lead a spade. East plays low, and declarer plays the jack, West following low. A club to the jack, and another spade off dummy. This time, East should win, and continue hearts, declarer ruffs leading to this position:

Declarer draws East's last trump, pitching a club from dummy, then runs his clubs, West getting caught on the last club: If West ruffs, he is endplayed, and if he pitches, he only gets his spade trick.

This is fundamentally the same end position as in our first example. The difference here is that declarer's trump suit was bad enough that West always had a natural trump trick, so maybe it was wrong to force declarer to ruff a heart? What if, instead, the defense adopts a passive defense, leading clubs at every opportunity?

Declarer wins the first club in dummy, and leads a spade. East ducks, declarer wins the jack, and crosses with a diamond and leads another spade.

East flies the ace and continues clubs. Declarer wins in hand, cashes the spade king, and exits a spade to West.

West can safely exit in hearts or clubs. Declarer wins and runs all his non-diamond winners. On the last club, the situation is: West cannot pitch a diamond, so he must pitch a heart.

Likewise, East cannot pitch a diamond (or declarer can pin the ten by leading the jack.) So East must pitch a heart. Now declarer exits in hearts and the defense is forced to break the diamond suit, giving declarer an extra trick in the suit.

In fact, declarer can engineer one of these two end-positions whatever the defenders do.

[ Special thanks to David DesJardin, for this analysis, and Richard Pavlicek for pointing out that my original analysis was wrong. ]