Source: Bridge News
(1) Kaplan Interchange
After an opening bid of 1
, there is an advantage to switching the 1
and 1NT (forcing) responses. This is called the Kaplan Interchange. Suppose responder does NOT have spades but does have a typical 1NT force. Playing standard responses, you cannot play in 1NT, because that bid is forcing.
However if you play the Kaplan Interchange, responder bids 1 with those hands, and opener with most minimum 5332 hands can now rebid 1NT to play, if responder agrees that is a good spot.
The disadvantage is that when responder DOES have spades he must bid 1NT forcing, so the partnership cannot play 1NT (with normal methods they can, with opener rebidding 1NT— 1-1 – 1NT). However the advantage outweighs the disadvantage, because responder will NOT have spades more often than he will have spades, so you will be able to settle in 1NT more often. The interchange is not needed if you play 1NT as semi-forcing.
(2) Support Doubles and Redoubles
Used by opener to show exactly 3 trump support for responder’s suit, whereas a direct raise shows 4 trump support. In the auction 1
/P/1/1 // (?), 2 shows four trumps whereas double would show exactly three trumps. A redouble can be used in the same manner. In the auction 1 /P/1/X/ (?), 2 shows four trumps and the Support Redouble shows exactly three trumps.
(3) Suction
Suction is an increasingly popular defensive system to a 1NT opener. The suit bid shows either (1) the suit above it, or (2) the other two suits. 2 = diamonds, OR hearts and spades. 2
= hearts, or spades and clubs. 2= spades, or clubs and
diamonds. 2 = clubs, or diamonds and hearts. 2NT shows the other two-suiter possibilities, pointed diamonds and spades, or rounded clubs and hearts. When the overcaller has a one-suiter, suction acts as a transfer and the opening 1NT bidder find himself on lead. Partner will almost always bid the next suit. If overcaller bids 2 (hearts or spades and clubs), partner will usually bid 2 which overcaller will pass or raise if he has hearts. If he has the twosuiter, he will bid 2, and partner will pass or raise or correct to clubs. Note if 2 is passed out, the NT bidder is on lead.
(4) Negative Free Bids
The auction has been 1 – 2 – (?) to you as responder. You hold KQ10xxx/xx/xxx/xx. Using standard methods responder needs about 10 or so HCP to bid 2 in this position, so that bid is out, leaving a negative double as the only alternative (or pass). After the double you hope to be able to get back into the auction at a later point to show your spades. However sometimes the opponents will preempt and make it difficult and dangerous for you to bring them in later. Playing Negative Free Bids, you are allowed to bid 2 directly with that previous hand. A 2 response would show about 5 to 11 HCP. The illustrated hand is about as weak as the bid should be.
Now you might wonder what one does with a GOOD 2 bid holding maybe KQ10xxx/xx/AKx/xx. With that hand, you make a negative double. Now when you bring spades into the picture later in the auction, it is far safer to do so, and opener will treat your spade bid as gameforcing, showing 12+ points.
Playing Negative Free Bids, you also make ‘standard’ negative doubles, so if responder held say Kxxx/xx/KQxx/xxx, he would still double. The double does not promise a big hand … the big hand is revealed later in the auction, after the
double, when responder bids his suit.