How you bid depends to a significant degree on the scoring method. How many times have we heard that one?

In the first Gaymsters Swiss of 2002, this classic hand reared its ugly head. Hands which fit this rule happen quite often, so keep this concept handy.

In both rooms, North-South waltzed into this eminently makable slam and made it. However, one East heard an interference bid* from his partner. Understandably, his expectation of beating the slam increased greatly and he doubled the final contract based on the ownership of two kings, four trumps, and partner's assumed defensive value. Relying on the last of these three factors to make a close double is a very risky business when playing IMPs. Reason: the risk-reward ratio that IMP scoring presents is against you.

By definition, a "close" double is one where your expectation is a one-trick set. In the example hand, East's two kings total one trick (using the defensive trick table). His four trumps are not a trick (J 10 9 8 for example, would be, but only in the trump suit); so he is relying on whatever is behind partner's bid to furnish the setting trick - a close double.

Now let's look at the various scoring risks and rewards.

They make 6 vulnerable, undoubled: -1440.
They make 6 vulnerable, doubled: -1660.
Risk: -220 (six IMPs to the bad guys).

We set 6 vulnerable one trick, undoubled: +100
We set 6 vulnerable one trick, doubled: +200

Reward: +100 (three IMPs to the good guys)

The risk-reward ratio of a close double is against you by two-to-one. This ratio also applies or gets even wider with games and parts scores. To prove this out, try substituting other contracts for the one above and translate the results.

Guidelines for Penalty Doubles at IMPs

• No matter what partner has bid, don't count on partner's hand for the setting trick. If partner's hand will yield more than the setting trick, it's not a close double.
• In a highly competitive auction (you have two suits and they have two suits), it's usually better to take the push and bid to a higher level than to double the opponents.

* West used "Michaels" — a convention which in the actual auction promises a two-suited hand composed of the unbid major and an unspecified minor. Partnerships which use Michaels are usually better off if they have a standing agreement about how many defensive tricks a Michaels bid promises. Without this agreement, partners will never be able to make reliable doubles no matter what the form of scoring.