While there are many conventions to help you reach the best contract,
sometimes using them can be fatal. Take a look at this one.
Scoring: Matchpoints (Pairs)
Hand #35
Dlr
E
Vul
N-S
102
K8
KQJ83
AJ96
KJ9876
62
Q10853
54
J109532
104
742
AQ3
AQ764
A975
K
West
North
East
South
Pass
1
2*
DBL
2
Pass
Pass
3
Pass
3
Pass
4
Pass
6NT
All Pass
*Michael's Cue bid
BIDDING: West's cue bid
showing spades and a minor certainly started something. North
doubled to deny heart support but show a good hand. East ran to 2 and
hoped for the best. With
no clear direction, South passed to see what North would do next.
After hearing 3 from his partner, South forced
again
with a cue bid. North next showed clubs and South leaped to the
slam to protect the spade queen from the opening lead.
PLAY: West guessed to
lead a low club won by South's king. Declarer could count eleven tricks
and was fairly confident from the bidding that the hearts would break
badly. However, West was marked with both the spade king and the
club queen so an endplay might be possible. First, declarer
played the top three honors confirming the bad heart break. Next,
he played all five diamonds and with the lead in dummy, was down to
this ending: North: 102 AJ
South: AQ3 7.
West was doomed; his last four cards were: KJ Q10.
Declarer could play ace and another spade for a club return or the ace
and another club for a spade return. Either way, declarer would
make his slam. Without the revealing 2 cue
bid, declarer might have tried to make the contract by taking the spade
finesse.
This is not to say you should not use the Michael's cue bid or other
tools, but rather realize that like the preempt, they are double-edged
swords which may cut you. Note 7 can be made only if played
by South. A heart lead would defeat it if declared by North.