North-South vulnerable.  East deals.
                              NORTH
                              S: A K
                              H: A J 2
                              D: K Q 10 8 7 6
                              C: K 4
            WEST                             EAST
            S: Q 10 6 2                      S: 7 5
            H: 9 8 6 5                       D: 10 7 4
            D: V o i d                       C: J 9 5 4 3
            C: Q J 10 9 6                    H: 8 7 5
                              SOUTH
                              S: J 9 8 4 3
                              H: K Q 3
                              D: A 2
                              C: A 3 2
                   EAST   SOUTH    WEST   NORTH
                   Pass    1S      Pass    2D
                   Pass    2NT     Pass    4C   
                   Pass    4S      Pass    5C   
                   Pass    5H      Pass    6NT
                   Pass    Pass
     One of the true pleasures in bridge is to hold the North
hand and hear partner open the bidding.  In the system that
North-South were playing, the two no trump rebid by opener showed
five spades and no second suit.  After a conventional Gerber ace
and king asking sequence, North took a very conservative view and
bid a small no trump slam.
     The opening lead was the nine of hearts.  Declarer played
low from dummy and won the trick with the ace in hand.  The
contract appeared to be unbreakable until South played the ace of
diamonds and West discarded a small club.  There was no way to
recover and the result was down one.
     Let's count tricks.  Declarer has ten off of the top; two
spades, three hearts, three diamonds, and two clubs.  The best
source of additional tricks is the diamond suit.  As long as the
outstanding cards in that suit don't break worse that 4-1, five
tricks are assured. In the event, however, that a 5-0 split
occurs (3.9%), why not take out a little insurance?
     If you start with the ace, you can handle five clubs with
West, but not with East.  If, however, you go to dummy and play a
small diamond, you can never be defeated.  If East plays low,
play the deuce.  If East shows out, play the ace and finesse
against the jack-nine on the way back.  If East plays the nine,
win the ace and when West discards, concede a trick to East and
score up your slam.
     When your contract looks ice cold, think about what the
worst situation could be and play to avoid it.
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