[steve2005]

In Transfer Walsh 1♣ is either balanced 2+♣ not in the range of 1N/2N/2♣ or 4♣441 or 5+♣.
With the 1♦ and 1♥ bids being transfers showing a 4+ major.

In most versions of Transfer Walsh the 1♠ response is used to show 4+ or even 5+ diamonds. For example see https://en.wikipedia.../Transfer_Walsh

In one variation 1NT response is a balanced invitational hand around 10-12 hcp. In this case, the 1♠ response can include any length for the minors.

The one detailed write-up available in pdf at 21twalsh.pdf (mgoetze.net) the 1♠ response shows 4+ clubs.
This would seem to be more useful as it finds a club fit right away if opener has clubs.
This method also uses 2M and 3M bids to show a splinter with at least 5-4 in the minors. This seems like a good idea but has a flaw when opener is 44(32) and responder is (31)(45).

Any thoughts on the efficiency of which minor suit length to show with the 1♠ response to 1♣?

[HardVector]

I like the 1♠ bid to show 6+ hcp and deny a major. You primarily want to clarify opener's hand, are they balanced 12-14/18-19, or are they unbalanced with real clubs? If they show balanced, you can decide if you want to play in 1n or 2c with a minimum or show better hands with other bids. Showing 4 clubs right away doesn't seem as useful as finding out about what your partner has opened.

That allows 1n to show an unbalanced hand with 5+ clubs, and 2c to show diamonds.

[fromageGB]

Absolutely concur with HardVector (other than I like 5+ with my lack of 4 card major). If opener rebids 1NT 12-14 then 2♣ is to play, 2♦ to play, 2♥ is 11+ 5+ clubs (remember 1♠ denies a major), 2♠ is 11+ with 5+ diamonds, and 2NT natural invite, 3m is a natural slam invitation.

Given the options available with 1♠, the alternative bids of 1NT, 2♣ and 2♦ are not wanted naturally, so all can show both majors in one bid. I play 1NT as 54xx or 45xx 6+ hcp, 2♣ as exactly 4 cards both majors 11+, 2♦ as 5 cards both majors (any strength).

As 1♣ 2♣ is 44xx 11+, weaker 44xx hands reply 1♦ to show hearts, and over 1♥ (denying 4) then rebid 1NT to show 4 spades.

Before anyone quibbles over my 1♠ on 5+ hcp but 1NT needing 6hcp, 1NT is forcing, so if opener does not have a 4 card major he rebids 2♣ and then responder transfers to the 5. As it is forcing to the 2-level, I say 6+ while a simple 1♠ then pass 1NT is 5+ as it is at the one level. Choose your own values.

[mw64ahw]

Other: I'll only show a minor suit with 5+♣/♦ when (31)(54) or 6+ otherwise with a direct 2m, so 1NT shows ~6-10hcp, no major and at worst 22(54). This frees up 1♠ to be game invitational for me

[nullve]

I have played the following* in one partnership:

1♣: 11-13-or-17-19 if balanced. Forcing.

1♣-1N: can be thought of as a natural invite opposite a Woodsonian** 11-13-or-17-19 NT. (Opener rejects/accepts the invite with MIN=11-13/MAX=17-19, respectively.)
1♣-1♠: like a Walsh 1♦ response if unbalanced OR a balanced hand without a major not in range for the 1N response
1♣-1♠; 1N = 11-13-or-17-19 NT.

The point is to be able to stop in 1N opposite 17-19 BAL when there is no fit. For example:

Opener:

a) 12 BAL
b) 18 BAL

Responder:

c) 2 hcp, 3343
d) 8 hcp, 3343

a)-c): 1♣-1♠; 1N-P
a)-d): 1♣-1N; P
b)-c): 1♣-1♠; 1N-P
b)-d): 1♣-1N; 3N-P

* essentially an idea described by BBF contributors zenko (in 2010) and helene_t (a few years later)
** The original Woodson NT is a natural 1N opening showing either 10-12 or 16-18 hcp. (Yes, simultaneously!)

[helene_t]

4+ in a particular minor is not so useful, I think, you probably want to bid 1♠ with any 33(43) or 5m332 hand that can't bid 1NT for whatever reason (rightsiding, range of of 1NT, 1NT is artificial?)

So I think 1♠ is whatever is left over after we defined the 1NT and 2♣ responses. We play 2♣ as 10+ points with clubs as the system evolved from a natural system where we also played inverted minors, but it may be better to play 2♣ as diamonds and 1♠ as clubs-or-balanced.

[kgr]

helene_t, on 2022-January-06, 06:28, said:

4+ in a particular minor is not so useful, I think, you probably want to bid 1♠ with any 33(43) or 5m332 hand that can't bid 1NT for whatever reason (rightsiding, range of of 1NT, 1NT is artificial?)

So I think 1♠ is whatever is left over after we defined the 1NT and 2♣ responses. We play 2♣ as 10+ points with clubs as the system evolved from a natural system where we also played inverted minors, but it may be better to play 2♣ as diamonds and 1♠ as clubs-or-balanced.

This is how I play it. I will bid 1S with f.i.:
rightsiding NT: Axx=xxx=Axxx=Axx
GF with D: AKxx=Axx=AQxxx=x
Weak with D: xx=xxx=AQxxxx=xx (after 1NT we bid then 2C as a puppet to 2D)