[gambolero]

If opener can support responder's major with 3 cards when unbalanced what is a good structure for continuing?

[helene_t]

If 3-card raises are made only with unbalanced hand you may agree that
1m-1M
2M-2N
is an asking bid and if opener now bids 3m (or 3♣ when his opening suit was diamonds) we can still stop in 3m (and opener's 3♣ is nonforcing if his opening suit is diamonds), but in all other situations the only partscore we can stop in is 3M.

If responder bids something else instead of 2NT, it shows five cards in the major so the major is trump. (Of course if responder bids 3NT directly it is choice of game and opener will usually correct to 4M with 4-card support).

If the 3-card raise can be made with balanced hands as well, there is a case for 2NT by responder to be nonforcing but I don't think anybody plays that.

[PhilKing]

I play two structures in different partnerships, first the "natural" one.

After 1♣-1♥-2♥:
2♠ = nat f1. All continuations are natural.
2NT = GF relay.
3♣ = inv, can be and often is three-card support, since opener will have five when he lacks four hearts
3♦ = nat f1
3♥ = nat inv with five hearts
3♠+ = splinter

The Marty Bergen structure has 3♦ as NF canape, but I don't think that is realistic. Anyway, I would respond 1♦ in a natural system with a 4-6 10 count or similar. You can also play the relay as non-GF, in which case the responses would need to be altered a bit, with 3♥ showing a minimum weak NT with 4 hearts, but this only caters for responder being 3442 invitational.

After 2NT relay:
3♣ = nat 6 cards
3♦ = 1345 or similar
3♥ = max weak NT
3♠ = 4315
3NT = min weak NT, suitable for NTs
4♣ = 4225
4♦ = weak splinters
4♥ = min weak NT

Note that the min spade splinter is missing, which is the nature of the beast when one plays step 2 as the relay. If one is prepared to play 2♠ as the relay, then 2NT in response becomes the 4315 and 3♠ a splinter.

In my system heavy partnership, after 1♣-1"heart"-2♥:
2♠ = relay GF
2NT = NF with exactly 44 in the majors
higher = same as above

After 1♣-1"heart"-2♥-2♠:
2NT = balanced with 4♥ (then step 1 asks for doubleton)
3♣ = 6♣ (step 1 relay agreeing minor or no trumps step 2 relay agreeing major)
3♦ = 4315
3♥ = 1345
3♠ = 3415 or 4414
3NT = 1435 or 1444

Since I have 3 ways of raising to 2♥ there are sometimes shapes above that cannot exist, but this is the generic order in which they are shown. After a 1♠ response, everything works much the same.

[lowerline]

gambolero, on 2014-December-11, 06:02, said:

If opener can support responder's major with 3 cards when unbalanced what is a good structure for continuing?

Next step is GI+ relay. Other bids are GI+ with 5crd M and shortness in the bid suit.

After the relay:
e.g. 1m-1♠-2♠-2nt:

• 3m min with 3♠ & 5m (NF)
• 3om max with 3♠ & 5m
• 3M min with 4♠ (NF)
• 3oM max with 4♠ (but not see below)
• 3nt max 4-3-3-3
• 4m max 4♠6m
• 4om/oM max Splinter

S.