PN Open
Two hands from the Palmerston North Open with a common theme illustrate that
it is not always correct to lead your 'longest and strongest'.
The first was perpetrated against us by Amy Thomson. On lead against 3 NT she
spurned her five-card heart suit and led the ♠ K. This was spectacularly
successful when partner cooperated with jack-fifth. Note a heart lead,
simultaneously, knocks out partner's entry, establishes two heart tricks for
declarer, and gives declarer the time to set up their diamonds.
East's hearts are certainly her longest but its moot whether they are the
'longest and strongest'.
Board 10 East Deals Both Vul |
♠ | A 10 4 | ♥ | K 10 6 | ♦ | A Q 5 | ♣ | A Q 7 3 |
|
♠ | J 9 8 7 3 | ♥ | A J | ♦ | 9 8 7 | ♣ | 8 5 2 |
| |
|
|
| ♠ | K Q 2 | ♥ | 9 8 7 5 4 | ♦ | K 10 2 | ♣ | 10 6 |
|
|
|
♠ | 6 5 | ♥ | Q 3 2 | ♦ | J 6 4 3 | ♣ | K J 9 4 |
|
West | North | East | South |
Compton | Davidson | Thomson | Burrows |
| | Pass | Pass |
Pass | 1 ♣ | Pass | 2 ♣ |
Pass | 3 NT | Pass | Pass |
Pass | | | |
We did some double dummy analysis, similar to Bird and Anthias, to test the
best lead. We dealt 1000 hands consistent with the bidding and looked at the
double dummy result with forced leads from spades and hearts. The ♠ K lead
resulted in an average of 9.376 tricks for declarer while a heart lead resulted
in an average of 9.454 tricks for declarer. Further the ♠ K defeated 3 NT, 234
times in the sample whilst a heart lead defeated 3 NT only 213 times. While this
was a moral victory for the non-standard short suit lead neither difference
(average tricks and proportion defeated) were statistically significant.
Subsequently we did a larger sample of 10000 hands and there the spade lead was
a small, but statistically significant, amount better in terms of both beating
3 NT and the number of tricks for the defence.
Board 16 West Deals E-W Vul |
♠ | K 10 8 3 2 | ♥ | — | ♦ | J 10 6 5 | ♣ | A 9 6 5 |
|
♠ | A 7 | ♥ | J 9 7 5 | ♦ | K 9 8 3 2 | ♣ | 10 4 |
| |
|
|
| ♠ | 9 6 5 | ♥ | K Q 4 | ♦ | A Q 4 | ♣ | K Q J 2 |
|
|
|
♠ | Q J 4 | ♥ | A 10 8 6 3 2 | ♦ | 7 | ♣ | 8 7 3 |
|
West | North | East | South |
| Davidson | | Burrows |
Pass | Pass | 1 ♣ | 2 ♥ |
Pass | Pass | 2 NT | Pass |
3 NT | Pass | Pass | Pass |
A session later, I faced a similar problem. Again the lead from
honour-honour-ex was spectacular.
In fact I had additional information. West had waited out the ten seconds while
I had the stop card on the table and then decided to question my partner on the
meaning of 2 ♥. How it could help her decision - I do not know. What she was
thinking of bidding - I do not know. All those sort of questions can do is
convey information to the table which may help the opponents and constrain her
partner. Apparently her partner did not feel constrained as she made the gross
overbid of 2 NT. The expert I polled - an unbiased sample of one - said "I will
have to pass" when given the auction "1 ♣ (2 ♥) Pass (Pass); ?"
The laws require east to not choose from among logical alternatives one
suggested by the additional information. Partner having values certainly
suggests action rather than inaction. I believe 2 NT is taking advantage of the
unauthorised information and should be not allowed and punished under Law 73C.
On this occasion karma delivered -300 for the 2 NT bidder.
Again a statistical analysis of the double dummy results found that the ♠ Q
lead average 9.053 tricks for declarer and defeated 3 NT 391 times. This time
the difference compared with a heart lead was marked with the heart lead
resulting in 9.997 tricks (nearly a trick worse for the defenders) and defeated
the contract only 142 times. These were statistically significant.
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