As South, assume you are declarer in 6 NT on each deal.Can you find the correct line of play to guarantee your contract?
Win the opening heart lead and lead a diamond to dummys queen. Next lead the spade two. If this loses to the queen, you have 12 tricks (four spades, three hearts, three diamonds and two clubs). If the spade 10 wins, cross to dummy with a club and continue spades to drive out the queen.
Observe that it would be an error to take the spade finesse at trick two (a heart return removes your entry) or after unblocking diamonds and leading a second heart (you would have no further entry to your hand).
Win the spade ace then cash the spade queen-jack to discard both of your diamonds. It is then a simple matter to lead diamonds until an opponent takes the king. You have 12 sure tricks in the form of four spades, three hearts, four diamonds and one club.
Note that if you played diamonds in the normal fashion, an opponent could refuse to win the king leaving you short of entries to establish the diamond suit. You would then have to rely on a favorable club layout to make your slam.
Win the club lead and lead the spade queen. If this loses you have four spades, one heart, five diamonds and two clubs. If the spade queen wins, next lead the heart queen. If this loses you have two spades, three hearts, five diamonds and two clubs. Finally, if the heart queen wins, lead the club two and your 12 tricks now consist of two spades, two hearts, five diamonds and three clubs.
If you failed to play either major suit as stated, an opponent could defeat you by refusing to win.
© 1992 Richard Pavlicek