One of the distinguishing features of 2/1K is
the reliance on Opener rebidding hir major (e.g. 1S:2D:2S)
to imply a minimum--even with good support for Responder's
suit. In essence, then, the 2-over-1 response to a major
suit opening is treated in much the same way as Reverse
Drury, with Opener rebidding hir major to show a minimum.
This gives rise to the albeit oversimplifying acronym
Two Over One Bids Are (Reverse) Drury.
S- 65432 H- Ax D- Kx C- AQxx
After 1S:2C rebid 2S, not 3C.
If, after the rebid of a major, Responder is
still interested in knowing more, Responder will take
things slowly with a 2NT rebid. This allows Opener to
disclose any support for Responder's suit if Opener has
it. After, say, 1S:2D:2S:2NT:3D, Responder will know
that Opener has a MINIMUM hand with 4-card Diamond
support and 5+ Spades. Other rebids over 1S:2D:2S:2NT
are natural (given that 2S denied 5-3-3-2 types) except
one:
3NT = 6-3-2-2 type, doubleton in Responder's suit.
3C = 4 Clubs, minimum.
3D = 4+ Diamonds, minimum.
3S = 6-3-3-1-ish, short in Responder's suit.
3H = None Of The Above. 6 Spades & 3 Diamonds.
With all other hand types eliminated, "None
Of The Above" (i.e. "NOTA") here will mean a hand with
6+ Spades and 3 cards in Responder's suit. After a 2C
response to a major suit opening there will be two
NOTA bids. For example, after 1S:2C:2S:2NT we'll see:
3NT = 6-3-2-2 type, doubleton in Responder's suit.
3C = 4 Clubs, minimum.
3S = 6-3-3-1 type, short in Responder's suit.
3D or 3H = None Of The Above.
Here again, the NOTA's show 3-card support for
Responder's suit and a 6+card major. Given TWO choices,
though, Opener will bid hir longer/stronger of the two
unbid suits.
S- AKxxxx H- xxx D- x C- AJx
After 1S:2C:2S:2NT rebid 3H.
S- AJ10xxx H- xx D- Qx C- KQJ
After 1S:2C:2S:2NT bid 3D.
Remember: the 2S rebid in the above examples
DENIED 4 Diamonds or 4 Hearts.
In the case of a Heart opening bid, there
remains the possibility of a 4-5 major 2-suiter. For
this reason, 3S over 2NT is required to show these
hands, and is NOT a NOTA bid. After 1H:2C:2H:2NT we
may see:
3NT = 6-3-2-2 type, doubleton in Clubs.
3C = 4+ Clubs, minimum.
3H = 6 Hearts, perhaps 4S, 0-2 Clubs.
3S = 4-5 in the majors.
3D = None of the above. Hence, 6 Hearts, 3 Clubs.
After 1H:2D:2H:2NT, there is no NOTA. Hence,
we will see:
3NT = 6-3-2-2 type, doubleton in Diamonds.
3C = 4+ Clubs, minimum.
3D = 3+ Diamonds, minimum. 9+ red suit cards.
3H = 6+ Hearts, short in Diamonds.
3S = 4-5 in the majors, 0-2 Diamonds.
