[pescetom]

Here in Italy it is almost universal to play that a 2♣ response to 1 in a suit is game forcing and semi-artificial: may be clubs but may also be balanced or a hand with fit that intends to raise opener's suit on next round (Jacoby 2NT is unheard of).

I've noticed that some players from out of town are now taking this a step further by playing that after a 2♣ response, a 2♦ rebid by opener limits his hand to 12-14 (or similar), over which 2NT by responder asks opener to continue to describe his distribution (3M shows a 4 card major, 3N balanced etc). Any rebid except 2♦ now promises 15+ and seems to retain it's normal meaning, so 2M shows a 4 card major, 2N is presumably 18-19 balanced and so on.

Is this a known scheme with a name, or a variation on such?

Any thoughts on its validity compared to normal 2/1 follow-ups?

[My first thoughts, FWIW. I'm not very excited about the range split, although it would certainly be useful at times. The NT auction is more nebulous, but that probably does no harm in 3NT at MP.I can see the advantage of hiding responder's hand and making him declarer in NT. I'm a bit surprised they give up this advantage when a 4-4 major fit emerges - replying to 2NT in transfer would obtain this and other benefits it looks to me.]

[mikeh]

In my main partnership we use the 2D as artificial, showing precisely a 5 card major. That resolves the perennial debate over whether 2M is the default rebid with a 5 card major, no side suit, and positionally wrong for notrump or whether 2N is the default. Now 2M shows 6+ and 2N shows some 5332 with stoppers

[smerriman]

What do they bid with 15 and 4 diamonds? Jump shift to 3♦?

[pescetom]

 smerriman, on 2023-November-10, 12:34, said:

What do they bid with 15 and 4 diamonds? Jump shift to 3♦?

I would guess so (I haven't had a chance to discuss it, beyond explanations of actual bids at the table).

[DavidKok]

There are multiple different schemes for 1M-2♣. If you are curious about options here I could recommend some. Generally using 2♦ as an artificial rebid is beneficial - clarifying the diamonds isn't a very high priority, while saving space is. In my opinion one important question is to decide how much work you are willing to put into this - once you start introducing artificial rebids the sky is the limit. I'll list some generic questions and then options.

Questions:

• If you play 2♦ as a minimum, does this include 55 hands, and/or hands with a minimum in HCP but extra length in the major and decent playing strength? For all you know it could be a misfit auction, but showing extra shape immediately has advantages as well.
  
• In particular on 1♠-2♣; 2♦ do you want to exclude 4♥ hands from 2♦ perhaps, to let responder jump to the right game (3NT or 4♠) more often now that slam is remote?
  
• If 2♦ contains most/all minima, does it also contain other hands? E.g. does it do double duty as generic min or diamonds any, or perhaps include strong hands (say, 18-19 5M332) as well?
  
• What does 1M-2♣; 2NT show, now that minima make a waiting bid?

Options:

• 2♦ minimum, other bids natural and showing extras. Nonminima with diamonds rebid 3♦.
  
• Rebids are transfers.
  
• 2♦ minimum or diamonds, other bids natural.
  
• 2♦ minimum not containing hearts, 2♥ natural wide ranging, other bids natural and showing extras.
  
• One of the above but rebids of 2NT and up are transfers.
  
• 2NT is artificial and shows 5M5m.
  
• AMBRA-style: 2♦ minimum, 2♥ showing the other major (so 1♥-2♣; 2♥ shows spades), 2♠ showing 4(+)♦ and extras, 2NT showing 6(+)M (I don't remember where 18-19 BAL goes - I think it's 2♦ and if partner jumps to game you bid on).
  
• Have you considered inverting the scheme - 2♦ showing extras, higher bids showing a minimum and clarifying shape?

I've played some of the above and seen a number of variations on this. One big downside is that none of these schemes do well on 1M-2♦ or 1♠-2♥, so you are learning an entire new bidding system for a particular 2/1 GF auction. It is the most frequent one of the set, but still something you need sure footing for. At the very extreme you can play 1M-2♣ game forcing relay (a la GRAMMY, perhaps).

[johnu]

 DavidKok, on 2023-November-10, 14:41, said:

I've played some of the above and seen a number of variations on this. One big downside is that none of these schemes do well on 1M-2♦ or 1♠-2♥, so you are learning an entire new bidding system for a particular 2/1 GF auction. It is the most frequent one of the set, but still something you need sure footing for. At the very extreme you can play 1M-2♣ game forcing relay (a la GRAMMY, perhaps).

The 1M-2♦ and 1♠-2♥ are already relatively well defined, game forcing with 5+ cards in the responding suit. (assuming hands with only 4♦ are handled with a 2♣ response, or a Jacoby 2NT response with 4+ cards in the major). You are already well on your way to a descriptive natural auction.

1M-2♣ auctions are very undefined. Usually 2+ clubs (could even be 0+??? if not playing Jacoby 2NT), balanced or unbalanced, may or may not have primary major suit support. As you note, it is the most frequent of the set, by a wide margin, so it makes sense to me to add some artificial complexity to clarify the holdings.

[mw64ahw]

I know these schemes as Nebulous 2♣s as per https://bridgewinner...us-2c-response/ although not quite as you describe. For example after a min. response the next step up asks rather than 2NT

[DavidKok]

You can definitely use 1M-2♣; 2♦-2♥ (or 2oM, if you wish) as a re-ask. It's even possible to go all the way to a relay system, where responder keeps asking questions instead of describing their hand. The effectiveness of this depends on the context of the rest of the system, but on balance I think it is a lot less effective than people seem to think. One or two swaps in an otherwise natural dialogue is solid though.

 johnu, on 2023-November-11, 18:04, said:

1M-2♣ auctions are very undefined. Usually 2+ clubs (could even be 0+??? if not playing Jacoby 2NT), balanced or unbalanced, may or may not have primary major suit support. As you note, it is the most frequent of the set, by a wide margin, so it makes sense to me to add some artificial complexity to clarify the holdings.

That last comment is the key point, in my opinion. If you have a scheme that lets both opener and responder clarify their hand this can work very well. This requires a lot of work though, as you need to have a good auction for every possible pair of opening and responding hand type. In my experience people usually present a half-baked relay idea, maybe one or two rounds down the most frequent paths or a copy of symmetric, and then give up and hope the rest of the system isn't tested in actual play. Introducing artificiality here can definitely gain and I've listed a number of ways to begin to go about it. Personally I think anything more involved than 'a few simple swaps' (which already is surprisingly complex) is going to be a lot of effort for marginal gains, and definitely non-marginal losses when starting out. It also doesn't help that this auction start is infrequent (I think you'll have a 2/1 auction on maybe 4-5% of all deals, let alone this specific one) and will often be a 'boring' choice of game decision (check for 8 card major fits then sign off in 3NT). So it'll be a complicated and long chunk of system, you won't get to practice it that much, even if you master it it won't come up that often, and when it does come up it often won't gain.

As a minor footnote, I played 1M-2♣ 0+ that wasn't even forcing to game (it also contained 10-11 5(+)♥ over 1♠, and 10-12 balanced no-fit invitational over either major). This was arguably even more complicated than the game forcing options, but (I think because the auction was so rare) we didn't suffer significant losses on it even if things did go wrong occasionally.

[pescetom]

 mw64ahw, on 2023-November-12, 23:01, said:

I know these schemes as Nebulous 2♣s as per https://bridgewinner...us-2c-response/ although not quite as you describe. For example after a min. response the next step up asks rather than 2NT

Thanks. I now remember reading that when it was written, but it was well over my head at the time.
I can see some merits (and defects) in this advancing scheme, but it is too memory intensive for any of my potential partners right now.

[pescetom]

 johnu, on 2023-November-11, 18:04, said:

The 1M-2♦ and 1♠-2♥ are already relatively well defined, game forcing with 5+ cards in the responding suit. (assuming hands with only 4♦ are handled with a 2♣ response, or a Jacoby 2NT response with 4+ cards in the major). You are already well on your way to a descriptive natural auction.

1M-2♣ auctions are very undefined. Usually 2+ clubs (could even be 0+??? if not playing Jacoby 2NT), balanced or unbalanced, may or may not have primary major suit support. As you note, it is the most frequent of the set, by a wide margin, so it makes sense to me to add some artificial complexity to clarify the holdings.

You are certainly right about 1M-2♦ and 1♠-2♥ promising 5+cards being well defined and leading to descriptive more or less natural auctions and the players I mention have not given them up or changed them as far as I can see.

You alre also right about the higher frequency of 1X-2♣, of course, but if there is anything I would like to better clarify it is in the 1m-2♣ auctions rather than 1M-2♣ with primary major suit support, which work just fine in my experience (maybe hard to imagine if one is used to Jacoby 2NT or playing without Fast Arrival).
Although I guess that an advancing scheme like the one I describe in OP still has some merit if it enables us to leak less information to the opponents during routine game-only auctions, even though it will not often help us to reach more precise contracts as far as I can see (and sometimes the opposite).

[DavidKok]

The scheme linked there is very similar to Ambra, and many of the continuation schemes are based on or related to the Ambra relay. One advantage is that the system (I'll let you guess what the name is) uses the same relay after a number of starts to the auction, so the high memory load is somewhat justified by the increased frequency. One disadvantage is that the scheme is not very good (in my opinion), and also caters to 1M-2♣ being 9+ (hence the need for an immediate negative) with many wasted auctions and suboptimal allocations after 1M-2♣; 2♦ in a 2/1 GF context. It also splits the opening ranges into weak (11-15) and extras (16-21), which is a pretty uncomfortable range for slam investigation no matter what your strength is. You can modify this by a point or two, but the fact remains that primarily shape-showing relays are not a great design choice over a standard opening. I strongly prefer getting back to natural bidding at an early opportunity on these 2/1 auctions.

[mw64ahw]

 pescetom, on 2023-November-13, 10:10, said:

Thanks. I now remember reading that when it was written, but it was well over my head at the time.
I can see some merits (and defects) in this advancing scheme, but it is too memory intensive for any of my potential partners right now.

I've tweaked it as you can see from the final comment on the article, and I find it structured to cover the various hand shapes so don't struggle with remembering. Minimum for me is 11/12-14 balanced or <14 not-balanced, but can be higher. 15-17 balanced go via 1NT so this is excluded.

[DavidKok]

 pescetom, on 2023-November-13, 10:29, said:

If there is anything I would like to better clarify it is in the 1m-2♣ auctions rather than 1M-2♣ with primary major suit support, which work just fine in my experience (maybe hard to imagine if one is used to Jacoby 2NT or playing without Fast Arrival).
Although I guess that an advancing scheme like the one I describe in OP still has some merit if it enables us to leak less information to the opponents during routine game-only auctions, even though it will not often help us to reach more precise contracts as far as I can see (and sometimes the opposite).

My experience is that the difference in information leak is marginal. The 1M-2♣; 2♦-3NT/4M auctions are rare and always a risk, as the 2♦ generic minimum rebid can still be pretty extreme shape. Since responder did not promise or deny a fit opener is basically reduced to counting Milton's for their first rebid, and it is highly unlikely that you can rule out slam and find the correct game as early as the second round. If you want to reduce the amount of information leakage I highly recommend splitting out a number of weak shapely hands (for starters, all 55's regardless of strength) so that the 2♦ rebid becomes 'a boring minimum'. This puts more pressure on every other part of the scheme, but conceals more information on the quick game auctions.
I play balanced club, unbalanced diamond with 1♦-2♣ being 5(+) and GF. 1♦-2♣ is an awful start to the auction, and I think you should take any system advantage you can get. Playing a [5+ or 4441] 1♦, or an unbalanced 1♦, greatly simplifies matters. If your 1♦ is frequently balanced you might be reduced to some pretty unpleasant schemes. One popular alternative here at the moment is to use 1m-1NT as a game forcing relay, which frees up the 2♣ response for some other hand types. I think this 1NT is fine over 1♣ and bad over 1♦, but the current top circuit in the Netherlands seems to think it effective.
I also have one of the most complicated and detailed (but possibly also effective) continuations over 1♣-2♣ on file, in case you desperately need a headache. Among other things it includes a scheme for playing the 2M Moysian rather than 2NT or 3♣.

[pescetom]

 DavidKok, on 2023-November-10, 14:41, said:

There are multiple different schemes for 1M-2♣. If you are curious about options here I could recommend some. Generally using 2♦ as an artificial rebid is beneficial - clarifying the diamonds isn't a very high priority, while saving space is. In my opinion one important question is to decide how much work you are willing to put into this - once you start introducing artificial rebids the sky is the limit. I'll list some generic questions and then options.

Thanks, but devising a better mouse trap than this one is not on my radar for now: it would be an enticing project, but I already have a shelf full of completed projects which I haven't afflicted current partners with yet.
My interest was more to see if this one is something common but not on the books that had just not reached my neck of the woods yet (I gratefully remember the first time someone alerted and explained responder's rebid of 2♦ as "XYZ" and I nodded knowingly making a note to google it later ). I gather not.
Although now we are discussing it, I am keen to understand its strengths and weaknesses and if we can defend better against it in some way.

Having said that...

 DavidKok, on 2023-November-10, 14:41, said:

Questions:

• If you play 2♦ as a minimum, does this include 55 hands, and/or hands with a minimum in HCP but extra length in the major and decent playing strength? For all you know it could be a misfit auction, but showing extra shape immediately has advantages as well.
  
• ..
  
• If 2♦ contains most/all minima, does it also contain other hands? E.g. does it do double duty as generic min or diamonds any, or perhaps include strong hands (say, 18-19 5M332) as well?
  
• What does 1M-2♣; 2NT show, now that minima make a waiting bid?

I think I would want to keep it simple and play 2♦ as a minimum (excluding inverting that too) without containing any strong hands. So 1M-2♣; 2NT would show the 18-19 5M332.

 DavidKok, on 2023-November-10, 14:41, said:

2. In particular on 1♠-2♣; 2♦ do you want to exclude 4♥ hands from 2♦ perhaps, to let responder jump to the right game (3NT or 4♠) more often now that slam is remote?

I miss your point here. Why not keep it simple and show secondary hearts in a minimum hand, and what stops responder jumping to 3NT or 4♠ over 3♥?
If I was going to change something in this respect, I would rather bid 3♦ after 2NT to show hearts, so that responder with secondary suit fit and slam interest can complete the transfer at level (and rightside the contract, even if in this particular case opener's spades control will be no surprise).

[nullve]

In my system

1M-2♣

could be a limit raise, so since I want to be able to

* stop in 2M if Responder has the limit raise
* use 2♥ as a GF relay over 1♥-2♣; 2♦ as well as over 1♠-2♣; 2♦,
* use 2♠ as a GF relay over 1♠-2♣; 2♥ as well as over 1♥-2♣; 2♥

I don't play any of the two "standard" variants

a) 1M-2♣; 2♦: includes most (all?*) hands on which Opener would like to stop in 2M opposite the limit raise

and

b) 1M-2♣; 2M = to play opposite the limit raise

but a mixture,

1♥-2♣; 2♥ = to play opposite the limit raise and the only way to stop below game

and

1♠-2♣; 2♦: includes all hands on which Opener would like to stop in 2♠ opposite the limit raise

.

Note that all auctions are GF unless Opener transfers to the other major.

[DavidKok]

 pescetom, on 2023-November-13, 11:38, said:

Although now we are discussing it, I am keen to understand its strengths and weaknesses and if we can defend better against it in some way.

I don't think there's much defending to be done (edit: having read on, I think nullve's system is a nice counterexample and can be challenged), other than to pay attention to the inferences of the auction. Usually opener will share a lot of information about their hand. Be careful if they explain that responder 'only relayed and hasn't shown any hand type' - often responder had relay breaks available and chose not to use them, which allows for negative inferences.

 pescetom, on 2023-November-13, 11:38, said:

I miss your point here. Why not keep it simple and show secondary hearts in a minimum hand, and what stops responder jumping to 3NT or 4♠ over 3♥?
If I was going to change something in this respect, I would rather bid 3♦ after 2NT to show hearts, so that responder with secondary suit fit and slam interest can complete the transfer at level (and rightside the contract, even if in this particular case opener's spades control will be no surprise).

The idea is that on 1♠-2♣; 2♦-? responder now does still not have a clear picture about 3NT vs 4♠ vs 4♥. Most of the time one of these three contracts can be eliminated, but rarely two (and sometimes none). This means responder has to ask for a further round of information, often getting an answer that is more helpful to the defenders than to responder. By allowing 1♠-2♣; 2♥ to be a minimum (so that the 2♦ rebid denies hearts) responder can usually at least rule out 4♥, and they can decide to simply blast 3NT more often.

[pescetom]

 DavidKok, on 2023-November-13, 15:03, said:

I don't think there's much defending to be done (edit: having read on, I think nullve's system is a nice counterexample and can be challenged), other than to pay attention to the inferences of the auction. Usually opener will share a lot of information about their hand. Be careful if they explain that responder 'only relayed and hasn't shown any hand type' - often responder had relay breaks available and chose not to use them, which allows for negative inferences.

As a Director and Laws/Regulations influencer I am painfully aware of the negative inferences issue. I was thinking more about maybe interfering with opener's hignly probable weak rebid (2♦ as takeout over 2♣?), but I guess pairs at this level will already have decided how to handle that and take advantage too.

 DavidKok, on 2023-November-13, 15:03, said:

The idea is that on 1♠-2♣; 2♦-? responder now does still not have a clear picture about 3NT vs 4♠ vs 4♥. Most of the time one of these three contracts can be eliminated, but rarely two (and sometimes none). This means responder has to ask for a further round of information, often getting an answer that is more helpful to the defenders than to responder. By allowing 1♠-2♣; 2♥ to be a minimum (so that the 2♦ rebid denies hearts) responder can usually at least rule out 4♥, and they can decide to simply blast 3NT more often.

I'm having a bad day as both posts and bridge results show, but sorry I still don't follow you.
Following my opponents' convention as I understand it:
1♠-2♣(GF); 2♦(min)-2NT(ask); 3♥-?
gives responder the information of a minimum 5=4=n=n which will identify any major fit and give a fair idea of what to risk if not. Yes they might well lack a minor stop, but going to 3NT without spelling it out is part of their approach and may well be advantageous overall at MP (I seem to remember you arguing much the same in the past).
Maybe the difference is that playing 1♠-2♣; 2♥ as a minimum (or 1♥-2♣; 2♠ as not) is not on my radar, whatever it hopes to achieve.

[DavidKok]

 pescetom, on 2023-November-13, 16:16, said:

As a Director and Laws/Regulations influencer I am painfully aware of the negative inferences issue. I was thinking more about maybe interfering with opener's hignly probable weak rebid (2♦ as takeout?), but I guess pairs at this level will already have decided how to handle that and take advantage too.

While minimum for an opening, you are still entering at the 2-level in a game forcing auction. If you were going to bid you should almost certainly have done so last round. While the nebulous club is less descriptive (to say the least) than a natural bid it still conveys some information. Expert pairs will likely either skin you alive if you bid here, or thank you for the extra round of bidding and use their pass/double agreements to maximum effect.

 pescetom, on 2023-November-13, 16:16, said:

I'm having a bad day as both posts and bridge results show, but sorry I still don't follow you.
Following my opponents' convention as I understand it:
1♠-2♣(GF); 2♦(min)-2NT(ask); 3♥-?
gives responder the information of a minimum 5=4=n=n which will identify any major fit and give a fair idea of what to risk if not. Yes they might well lack a minor stop, but going to 3NT without spelling it out is part of their approach and may well be advantageous overall at MP (I seem to remember you arguing much the same in the past).
Maybe the difference is that playing 1♠-2♣; 2♥ as a minimum (or 1♥-2♣; 2♠ as not) is not on my radar.

You are dealt ♠Kx, ♥Qxxx, ♦Qxx, ♣AKxx. Partner opens 1♠, you are optimistic about slam and bid 2♣. Partner bids 2♦. Slam has become quite remote, but you might belong in any of 4♠, 4♥ or 3NT. So you have to ask for more info (2NT, or 2♥), and partner rebids 3♣. Now 4♥ is out of the picture and you've pinpointed a red suit lead against 3NT, and 4♠ in the 5-2 fit doesn't look great. Are you asking more info (but what for?), bidding 3NT, or something else?
If 2♥ could have been a minimum so that 2♦ denies extra major suit length you could have bid 1♠-2♣; 2♦-3NT, concealing your heart length and possible diamond weakness. More generally, if 1♠-2♣; 2♦ shows any minimum (use any criteria for evaluation you prefer), responder will often have to ask for shape information next with 4 hearts, or a side suit weakness. A lot of the time partner won't have the extra length in a major suit you are looking for, and you end up bidding 3NT anyway but have now partially exposed declarer's hand. One possible remedy is to immediately split out some hands with extra major suit length from 2♦, so that it is no longer any minimum but rather a 'boring' minimum. This allows responder to jump to 3NT or 4M on the second round often.

[pescetom]

 DavidKok, on 2023-November-13, 16:35, said:

You are dealt ♠Kx, ♥Qxxx, ♦Qxx, ♣AKxx. Partner opens 1♠, you are optimistic about slam and bid 2♣. Partner bids 2♦. Slam has become quite remote, but you might belong in any of 4♠, 4♥ or 3NT. So you have to ask for more info (2NT, or 2♥), and partner rebids 3♣. Now 4♥ is out of the picture and you've pinpointed a red suit lead against 3NT, and 4♠ in the 5-2 fit doesn't look great. Are you asking more info (but what for?), bidding 3NT, or something else?

I am not optimistic about slam but bid 2♣ anyway, then opt for 3NT like the rest of the field.
But I see your point, will think about it thanks.

[nullve]

 DavidKok, on 2023-November-13, 16:35, said:

You are dealt ♠Kx, ♥Qxxx, ♦Qxx, ♣AKxx. Partner opens 1♠, you are optimistic about slam and bid 2♣. Partner bids 2♦. Slam has become quite remote, but you might belong in any of 4♠, 4♥ or 3NT. So you have to ask for more info (2NT, or 2♥), and partner rebids 3♣. Now 4♥ is out of the picture and you've pinpointed a red suit lead against 3NT, and 4♠ in the 5-2 fit doesn't look great.

To reduce the information leakage on hands like this, one could play

1♠-2♣; 2♦-2♥ = strong relay
1♠-2♣; 2♦-2N = (Staymanesque) weak relay, mostly (only?) asking about major suit length

and have an auction like

1♠-2♣
2♦*-2N**
3♣***-3N****
P

* any MIN
** weak relay
*** neither 4+ H nor 6+ S
**** contract

.