[johnu]

Winstonm, on 2021-April-30, 19:56, said:

At what point in time did 2/1 game force start applying to a 1D opening? There is no forcing NT to use ergo, no 2/1. This has historically been played as an SAYC sequence, and 2C is only forcing to 2n or 3 of a minor.

I am either way out of touch or hopelessly confused.

I would guess that 1♦-2♣ became a game force when people started using 1♦-3♣ as invitational. You've got 2 invitational sequences, a 2NT response is the other, so you can create low forcing auctions starting at 2♣

[DavidKok]

I think both styles - 1♦-2♣ as 10+ and 1♦-2♣ as GF - are quite common. If you play 2/1 be sure to discuss this with your partner. As always I prefer the style advocated by Larry Cohen, where it is GF.

[TMorris]

Playing that silly Acol system I start with 2 ♣ and over 2 ♠ I bid 3 ♦ describing my hand. Still who would play that system.

[Douglas43]

As somebody who doesn't normally play 2/1 I've been finding a it difficult to handle the robots' intermediate jump shift to 3♣ or 3♦. I guess every system has gaps, and hands where responder has about 9+ to 11+ with a minor can be a challenge in 2/1l?

(If 2♣ is not GF, then 1♦ No 2♣ [2♥] 2♠ No 3♦ looks OK)

Sorry, missed Tmorris's post when I posted. Same point.

[Winstonm]

mikeh, on 2021-April-30, 21:54, said:

Originally 2C over 1D was not gf if followed by 3C. However, a large segment of 2/1 players now use 2C over 1D as gf. I've been playing it that way, with a number of partners, for many years and think it's probably now the more common approach.

Thanks for the response, Mike; however, that still makes little sense to me. 2/1 GF is a structure that is based on bidding 5-card suits and using a forcing NT to to handle a multitude of hand types that don't fit the system any other way. Without 1D-1N as forcing, 2C over 2D as GF is only a treatment and not part of the systemic bidding of 2/1.

I understand the principle behind the changes - the compromises come in the club suit basically - but I'm not sure that being able to bid 2C-3C forcing is worth the tradeoff.

But thanks again for the reply.

[Winstonm]

johnu, on 2021-May-01, 01:57, said:

I would guess that 1♦-2♣ became a game force when people started using 1♦-3♣ as invitational. You've got 2 invitational sequences, a 2NT response is the other, so you can create low forcing auctions starting at 2♣

I see two benefits: 1D-2C-2D-3D becomes forcing, and 1D-2C-2D-3C becomes forcing. The disadvantage? 1D-3C is hugely room-consuming with no known fit and no known strength in partner's hand. It is a picture bid without the compensating strength. I guess I'm old fashioned, but 1D-2C non-game-forcing never caused a problem for me.

[akwoo]

apollo1201, on 2021-May-01, 01:16, said:

I thought that in contested auctions involving a reverse (that might be a little shaded in the circumstances, you need to convey shape and reasonable amount of strength to partner when things get active around the table), the 2NT bid to « moderate » partner doesn’t apply anymore.

The auction

1C-(1S)-1N-(P)-2H

can be shaded, because responder never had a chance to bid hearts at the 1 level.

The auction

1C-(P)-1N-(2H)-2S

cannot be shaded, because responder had a chance to bid spades at the 1 level and didn't.

4th seat interference is very different from 2nd seat interference, because with 4th seat interference, opener can pass or double with various sorts of difficult hand types.

[mikeh]

Winstonm, on 2021-May-01, 09:00, said:

Thanks for the response, Mike; however, that still makes little sense to me. 2/1 GF is a structure that is based on bidding 5-card suits and using a forcing NT to to handle a multitude of hand types that don't fit the system any other way. Without 1D-1N as forcing, 2C over 2D as GF is only a treatment and not part of the systemic bidding of 2/1.

I understand the principle behind the changes - the compromises come in the club suit basically - but I'm not sure that being able to bid 2C-3C forcing is worth the tradeoff.

But thanks again for the reply.

The forcing notrump predates 2/1 gf, but is admittedly an integral part of the common response structures to 1M opening. However, to me the essence of 2/1 is the conservation of bidding space when responder has sufficient values to force to game, especially when if either opener or partner (or both) have extra values then slam or grand may be in the mix.

Bidding space is well preserved after 1D 2C as well, if 2C is gf. Indeed, as I have said on numerous occasions (but the notion is not original to me), 1D 2C is one of the more difficult areas of bidding theory, in terms of what opener needs for virtually any action. It’s tough enough, from a theoretical p.o.v., when 2C is gf. It becomes even tougher when it isn’t. I admit, in saying this, that one can usually muddle through without truly coherent structures, and for the vast majority of players, and hands, that’s good enough.

[pescetom]

mikeh, on 2021-May-01, 13:43, said:

The forcing notrump predates 2/1 gf, but is admittedly an integral part of the common response structures to 1M opening. However, to me the essence of 2/1 is the conservation of bidding space when responder has sufficient values to force to game, especially when if either opener or partner (or both) have extra values then slam or grand may be in the mix.

Bidding space is well preserved after 1D 2C as well, if 2C is gf. Indeed, as I have said on numerous occasions (but the notion is not original to me), 1D 2C is one of the more difficult areas of bidding theory, in terms of what opener needs for virtually any action. It’s tough enough, from a theoretical p.o.v., when 2C is gf. It becomes even tougher when it isn’t. I admit, in saying this, that one can usually muddle through without truly coherent structures, and for the vast majority of players, and hands, that’s good enough.

I agree totally with your reply, but am curious to learn that forcing NT predates 2/1. When was the origin and what was the driving force for this change?

[mycroft]

Not sure of the answer to this, but K/S isn't a 2/1 system at all (although most who still play it play some-to-most 2/1s GF), and the three keys are:

• weak NT
  
• 5-card majors
  
• forcing 1NT response

Precision originally was also not a 2/1 system, but always had forcing 1NT response with the 5 card majors (at least since Reese's book). Of course that's 15 years later than K/S.

Too young to know why, but I'm guessing the 5cM is the key - there's too many hands where you would be comfortable playing the 5-2 rather than 1NT, that don't have enough strength for (a standard American) 2/1. You lose the "race to 1NT", but you don't get stranded there with either the 5-2 or the long suit in responder.

[hrothgar]

pescetom, on 2021-May-01, 14:19, said:

I agree totally with your reply, but am curious to learn that forcing NT predates 2/1. When was the origin and what was the driving force for this change?

My understanding is that the forcing NT was originally conceived by Al Roth as part of the Roth Stone system and was later incorporated as part of Kaplan Sheinwold.

Neither of these systems featured 2/1 Game Forcing bids.

I'm not quite sure who originally came up with the notion of using a 2/1 as a GF. However, my impression is that this was popularized by Dick Walsh out on the West Coast and Bobby Goldman on the East Coast.

[mw64ahw]

jillybean, on 2021-April-30, 20:19, said:

---

3♥ would see us reach 3nt.

The full hand;

---

Tough one to bid the slam on. South's hand would be 'GF' for me with 10+hcp & MLT<=7.5. As North I would be looking for the marginal slam after the 'GF' bid, but end up in 5♦ as the slam exploration would show less than a 50/50 chance of it being made. I would skip 3NT as my bidding sequence would only find 3♥ between us.

[Winstonm]

hrothgar, on 2021-May-01, 15:00, said:

My understanding is that the forcing NT was originally conceived by Al Roth as part of the Roth Stone system and was later incorporated as part of Kaplan Sheinwold.

Neither of these systems featured 2/1 Game Forcing bids.

I'm not quite sure who originally came up with the notion of using a 2/1 as a GF. However, my impression is that this was popularized by Dick Walsh out on the West Coast and Bobby Goldman on the East Coast.

Richard,
I seem to remember a lot of talk about a Max Hardy book on 2/1 - this was in Santa Barbara around 1973

I just located this: it appears that we all had a piece of the 2/1 puzzle but this puts the picture together.

This post has been edited by Winstonm: 2021-May-01, 17:56

[hrothgar]

Winstonm, on 2021-May-01, 17:36, said:

Richard,
I seem to remember a lot of talk about a Max Hardy book on 2/1 - this was in Santa Barbara around 1973

I just located this: it appears that we all had a piece of the 2/1 puzzle but this puts the picture together.

Thanks for posting this.

Interesting. I associated Eastern Scientific much more with Bobby Goldman than Paul Soloway.