Artificial Interference: Lebensohl modifications:
unknown suit or suits:
if auction will return to responder at the 2-level, responder may pass and
use Lebensohl at second opportunity. if 3rd hand passes the relay, opener
one suit known - key on the known suit
two suits known - one suit is a major - key on the major; if at some point
responder has a choice of cuebids at the 3-level (Stayman), cue suit with
both major suits -
H cue shows H honor (if 2H, invitational only)
S cue shows S honor (if 2S, invitational only)
2NT shows honors in both majors
3NT denies major honors
Kirby for Big Overcall (17-20)
A jump reverse to a 1NT response to a minor suit opening shows a splinter
and is a suggestion for 3NT if the 1NT bidder has the suit comfortably stopped.
Weakness Signal After a Reverse
By a Responder who bid a suit at his first call: the cheaper of 2NT or
fourth suit following a reverse by opener is a weakness signal and may be
passed by opener.
Minor Suit Auctions:
NT Response Ranges
11-12 2N (denies 4 card support for the minor)
13-14 Two Step, either single raise or 2C over 1D; then 3N
Every Suit Up the Line Auctions (1C-1D-1H)
2S Artificial 4SF
After Single Raise of a minor, Opener's Rebids:
2 Major: Shows stoppers; denies stoppers in the other major
2NT: Shows stoppers in both majors, tends to deny clubs
3 agreed minor or 3C if D is agreed minor: denies stoppers in either major
1D - 2C Auctions.
Opener's rebids similar to rebids to Single Raise of the Minor, except that
2 of a major is more likely to show a suit.
Splinter warning: If opener's rebid is a major and responder's next bid
is 4 of either minor, it is a splinter in support of opener's major even
if it is into opener's original suit.
New Minor Forcing Modifications:
1. Holding 4H and 3S, show the 4 in the unbid major above showing 3 card
support for S.
2. Do not jump to 3 of responder's major with a maximum. Jump is invite,
3. 2S immediately over 1NT is weak.
4. A 2S rebid by the nmf bidder over a 2D or 2H response shows 6+ and is
A 2-level response to an opening bid after an overcall is the equivalent
of a standard american 2-over-1, i.e. 10+; it is forcing for one round,
but NOT forcing to game. subsequent bidding by responder can easily serve
as a further force (e.g. a new suit or a cue-bid).