[straube]

I've been looking at 1C (2m) interference. Many of us play transfers over this.

1C (2C) 2D shows 5+ hcps and 5+ hearts
2C (2C) 2H shows 5+ hcps and 5+ spades
1C (2D) 2H shows 5+ hcps and 5+ spades

In addition many of us play transfers over 1S interference.

So the question is whether opener should accept the transfer with a minimum hand and usually doubleton support. I've looked at a few hands (maybe 50) and it seemed to me that only around 10% of the time was this a very attractive option. Usually opener had a better option rebidding 2N or his own suit (nf).

I'm thinking...

accept the transfer-GF, no fit
.....responder rebids naturally, using the cue bid as a stuck bid
bid a suit, nf (bidding a suit at the 3-level is usually a 6-cd suit or a chunky 5-cd suit)
.....responder may pass or correct to 2N or force with any suit (including rebidding his suit) or cue bid
bid 2N
.....responder may pass or force with a new suit or cue bid. Should rebidding his suit be forcing? Don't think so as the cue bid is available.
raise partner's suit as GF fit
cue bid as a minimum raise
.....we have the intervening transfer bid as either a re-transfer or a game try. Not sure which is better.

So maybe someone could run a hand generator and see if they're finding the same thing.

[awm]

Here's my view on this. Opener's hands can be broken down as follows:

1. Balanced minimum without a great fit, might not have game.
2. Balanced extras without a great fit, enough for game
3. Fitting hands (if balanced, generally 4-support or extras), all enough for game
4. Shapely minimum without a fit, might not have game
5. Shapely hand with extras and no fit, enough for game

The first hand type will include between a quarter and half of 17-18 balanced hands (almost all 4333s, all 4432/5332s with doubleton in partner's suit, some 4432/5332s with three in partner's suit). Since 17-18 balanced is the most common strong club, these hand types should be a significant fraction. On these hands I want to retain the possibility of playing in two of partner's major.

The main tradeoffs here seem to be that straube wants to use transfer-accept as a forcing bid where we use 2nt. This puts him ahead on hand type 2 (responder has more room to describe and also knows he is in a GF). But it puts him behind on hand type 1 (can't play 2M), and also on hand type 5 (where 2♠ over heart transfer and 3m are both non-forcing, meaning opener has to relay and can't describe his hand). Further, the majority of the time hand type 2 will end in 3nt or four of responder's suit, and it's not clear to me we need extra space to sort out this hand.

[straube]

Maybe you could use 2-under transfers?

I'm just finding that the first step is too important and using it as nf is too infrequent.

I think you're right that it is awkward when opener wants to force with a suit and has to relay instead. However, much of the time he wants to make a nf introduction of his suit. Especially so if his suit is a minor and he can't bid it without forcing game. Maybe it's better to have transfer acceptance as the GF relay and 2M to be a 1-rd force. Is that better?

We had really complicated continuations...Rubensohl and so on and this is just a lot simpler.

[awm]

Here is what we play:

1. 2M acceptance = NF, doubleton or three-card support in a min balanced hand
2. New suit at two-level = F1, not necessarily extras though
3. 2NT = forcing; various hands
4. 3x = GF; natural other than cue

2NT is one of: 1. non-fitting min with a long suit to introduce at the three-level 2. non-fitting balanced hand too strong to accept the transfer. Continuations after 2NT:

1. Responder bids 3♣ if non-GF. Opener can now bid 3M to show a strong balanced hand with doubleton, or below 3M to play, or pass 3♣ to play.
2. Responder bids anything else. These are GF and as natural as possible, with 3♦ being potentially a punt on an otherwise awkward GF hand. Continuations natural.

[straube]

ok thanks. I couldn't see how to sign off in a lower ranking suit. What does opener use the cue bid for? Also I'm assuming that after 1C (2C) 2D P 2S that 2N is the only weakness signal; opener could rebid 3S to play.