Caroline Club is a forcing club system with canape major suit
openings. Hence it bases its theoretical underpinnings on previous
such systems. Blue Team Club, for example, is similar in some
important respects. Canape bidding may have been invented in France
in the 1940s but certainly owes its popularity to 1960s-era
Italians.
Caroline Club is a light opening system-- all ten point hands are opened.
It is probably preferable to use a lower range, but one basic
goal of Caroline Club--permissibility under the ACBL's GCC--required
a 10-point minimum for 1NT and perhaps a 1♦ opening.
Caroline's 1♦ opening includes a number
of possible hand types, as is customary with big club systems. All
of the 4441 hands are lumped into 1♦,
so the opening can be made with a singleton diamond. It is not possible to
use two-level bids for some of these hands because they are needed for
other purposes.
Two bids are two-suited and intermediate (except possibly for 2♣),
allowing one to show the backwards 54 hands unsuitable for a
canape opening because the major suit is longer than the minor. A
1♠ opening might show a 4-card spade suit with a 5-card minor.
The reverse distribution is shown with an opening 2-bid. For example,
2♠ shows 5 spades and 4 diamonds. Hence all two suited hands
can show the relative suit lengths easily, except for minor two suiters
which are ambiguous.
A basic goal of Caroline is to conceal the stronger hand from the defenders.
Toward this end, positive responses to 1♣ show suits different than
those bid, allowing the more powerful and less-defined hand to declare.
For example, 1♣-(p)-1&hearts shows a positive
response with spades while 1♣-(p)-1♠ shows
a positive response with hearts. Since a game contract will
generally have about two thirds of the strength in the 1♣ hand, it
seems prudent to arrange for that hand to declare. Furthermore, the
strong hand can withold distributional information as well.
A similar concept permeates Caroline's NT structure.
Caroline Club uses a basically natural approach within its systemic
structure. So various conventions and treatments can be integrated into
it. Much Caroline complexity comes from these add-ins rather than
from inherent requirements.
Major suit openings in Caroline can be four cards in length (if a longer
suit is present). Hence major suit fits are located quickly. Users are
advised to take advantage of this by quickly reaching game or consuming
bidding space as appropriate.
Caroline tends to propel users toward game. For example, 16+9 is
game forcing, as is 18+6. We would rather force opponents to set us than
to avoid contracts that are doomed on a double-dummy basis. Another
example would be 10+13 (minimum opening and 2NT response) which is
forced to at least the three level. Another rarified sequence could
be a minimum canape opposite a minimum 2/1: (e.g. 1♠-2♥-3m on 10 opposite 10). Some users have employed
Lebensohl here in an effort to sign off in 3m.
Caroline bids vary in point range between 1st and 2nd seats and in 3rd
and 4th seats. Almost all bids require an additional two points in
third or fourth seats, as partner is a passed hand and hence has a
maximum of nine points. This allows a similar structure both for 1st/2nd and for 3rd/4th openings. For example, 1♣ is 16+ in 1st and 2nd and
responder's hands are divided into non-game-forcing (0-8) and game
forcing (9+). If the same 16+ opening were used in 3rd/4th, responder
swould have the 0-8 hand most of the time with a small possibility of
exactly 9 points, which would be a systems engineering disaster. Instead,
the 1♣ bid is increased to 18 points in 3rd/4th seat, allowing
a division of responders hands into nonforcing (0-5) and game
forcing (6-9).
Strong club systems must be prepared to deal with interference.
Caroline uses a 16-point limit in 1st and 2nd seat, making it less
likely that opponents' can count on intervening in a likely game
auction as might be the case with a stronger minimum for 1♣.
However, intervention is nonetheless likely. Caroline's basic
philosphy toward interference is to ignore what calls
show but to deal with what calls were actually
made. Hence the system is designed to be impervious
to psychs or misbids, though at the risk of failing to acquire
potentially useful information about opponents shapes and strengths.
Such information should be assimilated by Caroline users, however.
As an example, consider 1♣-(1♥)-?. Caroline now defines an immediate
1♠ bid as a heart positive (5+ hearts and 9+ points), just as
would be the case sans interference. It is not necessary to
understand if the opponent's 1♥ bid
showed hearts, hearts or spades and clubs, or anything else. This can
be especially valuable if opponents adopt fert-like interference bids
or dual-meaning bids (a la Caroline's wonder bids), or if they become
confused over their methods.
One item that deserves some specific attention is that of dealing
with major two suiters. A 4=5=x=y hand opens 1♠ and rebids
2♥, as would be the case for canapes
with minor suits. The reverse case, 5=4=x=y, is not
treated with a special two bid but is instead bid out at the one level.
In order to do this, the hand must be opened with 1♥. Responder now makes a 1♠ bid with any responding hand with
at least three spades not suitable for a heart raise.
Since opener can not have exactly four spades when opening
1♥, responder bids a three-card suit to cater
to the possibility of a 5-card spade holding. This is in some ways an
analogous inference to that available to those who play the nefarious Flannery convention, in that certain length holdings are eliminated.
Cases in which the 1♠ response "picks off" the defender's best
fit is rarer than might be expected, since responder may have more than three spades or opener might have a spade canape. The 1M opening tends
to "pick off" the enemy suit sometimes, and this on a deal where
it was breaking badly.
Another item of theoretical interest is the fact that traditional
negative doubles and forcing bids are employed after an overcall of a
1 ♦ opening, since opener can have a
4432-like balanced hand (with 13-15). Over 1M openings, however, this
is switched to employ positive doubles and negative free bids. This works
well since opener will often have a canape suit and there might be a
total misfit.