March 2005 - 47

Matchpoint / IMP
strategy - part 6
Slam bidding at IMPs, like game
bidding, is governed by safety. The
difference between making 6 and
6NT is 70 points, 2 IMPs.
To bid an uncertain 6NT, confident that 6 is cold, risks a loss
of 14 or 16 IMPs (depending on
vulnerability) to gain only 2 IMPs.
At matchpoints, it's more complicated. To move from a probable
laydown small suit slam to a questionable 6NT may make sense,
provided that you feel confident that
the field will bid to the six level.
In effect, you are aiming to improve a 55% score to 95%, with the
downside being a 5% result. The bet
is to gain 40% while risking 50%,
slightly uphill odds.
Playing matchpoints, you hold
A K 6 2 9 7 K Q J 6 2 A 5
and open 1. Partner responds 1,
you rebid 1 and partner jumps to
3, invitational. How do you rate
your hand?
If you take a dim view, you sign
off in 3NT. If you react to your
splendid controls and trump quality,
you make a slam move, say 4NT.
Playing Roman Keycard Blackwood, partner shows one key card.
At matchpoints, there is little point
in stopping at 5: if 11 tricks are
the limit, you will lose to the 3NT
declarers when they score a mere 10
tricks.
Let's say that you are willing to
commit to a slam - will it be 6
or 6NT? Visualize a typical hand
for partner:
1. 4 3 A K 8 2 10 9 7 5 3 K 2.
Matching it to our
A K 6 2 9 7 K Q J 6 2 A 5,
we see an easy 12 tricks in diamonds
but only 10 in notrump. Perhaps partner will supply:
March 2005

2. Q 4 A Q J 8 2 10 7 5 3 K 2.
Then, both slams basically depend
on the heart finesse, so we may as
well play 6NT. Does this make 6NT
reasonable? Not really, because if
either slam makes, we are well ahead
of the field.
Try another problem: you hold
K 8 K 3 A K Q 6 3 K 9 8 2.
You open 1, partner responds
2, you mark time with a forcing
3 and partner rebids 3. This
time, it is easy to imagine slam with
all our great cards, plus a double fit.
A simple 4NT (Keycard Blackwood
for clubs, the first agreed suit)
elicits two key cards plus the Q.
Which slam looks best?
Given partner's 2 response, the
missing ace is likely to be in the
majors. This makes 6 dangerous
because an unprotected king may
be exposed to the opening lead. 6
overcomes that objection, but this
is a perfect time to bid 6NT - not
only for the extra points, but also
for extra safety.
Let's say partner was dealt:
7 5 A 8 J 8 6 4 A Q J 6 3
6NT has 12 top tricks, 6 runs the
risk of a club ruff when clubs divide
4-0 and 6 goes down on a spade
lead if the ace is offside. Slightly
alter partner's hand to
A 7 A 8 J 8 6 4 Q J 6 4 3.
6NT is still cold while 6 runs
the risk of a club ruff against certain
4-0 and 3-1 splits. Therefore, this is
the ideal spot for 6NT at any form
of scoring.
What about grand slams? At
matchpoints, the idea is to be right,
so, superficially, it would seem
proper to bid a grand slam offering
better than a 50% chance.
The field must, however, always
reach at least a small slam to elevate
your grand slam from average to top.
On most deals and in most fields,

INTERMEDIATE PLAYERS

Boehm on
Bridge

August Boehm
this is not a realistic assumption.
As a practical matter, bidding a
successful small slam usually earns
you an above-average score. Bidding
an uncertain grand slam risks turning a fine score into a zero. Similar
to the rubber bridge player, don't
bid seven unless you have massive
high-card points or are able to count
13 tricks.
At IMPs, here is the math: not
vulnerable, stretching to seven
stands to gain 11 when it makes or
lose 14 when it doesn't; vulnerable,
the upside is 13, the downside 16.
On a mathematical basis, that
makes the dividing line for bidding
seven around 56%, but it ignores
reality. Assume that you are playing
a team match and you sense a possible superfit grand - do you settle
for six or take the plunge? Take the
small slam bonus.
How can you be sure that your
opponents at the other table have
reached six?
Perhaps your partners derailed
them with a preempt. Perhaps their
system or judgment is not up to
your standard.
If they have languished in game,
you have already salted away a
double-digit swing by reaching six,
and your effort to land a grand slam
risks losing it all, merely to add a
couple of IMPs. At IMPs, bid your
grand slams very carefully.

47
Table of Contents for the Digital Edition of March 2005
