2/1 shape before strength? 2/1 methods
#1
Posted 2019-February-17, 07:26
In looking at the 'Must questions' as Lawrence calls them (is a 2/1 always GF, does a reverse/splinter etc after a 2/1 show extras and so on), I see a number of players advocating that the reverse etc are shape-showing only, no extra strength implied.
The searches I've done include a number of (old) discussions here, in which various people say '2/1 doesn't have to show the strength immediately', however I don't seem to be able to find anything on exactly how one would go about showing strength later.
An example may help, suppose the auction begins (uncontested): 1H - 2D - 2S - 3S
We got to 3S, showing shape, before we found a fit. If 2S shows nothing extra then the only inference we have as to strength is that responder's 3S said something different to what 4S would have said (I believe that for most 4S would be fast arrival, so 3S is stronger than 4S. Are cues by opener now strength-showing or simply co-operating with slam investigations?
We seem to be running out of bidding space to exchange information regarding strength. I'd be interested to hear how good players solve this 'problem' (not only the specific sequence above, but the issues raised by the shape-before-strength approach in general).
In the past when I've played 2/1 I've simply played reverses, new suits at the 3-level etc as strength-showing, as they would be in a non-2/1 system.
Thanks in advance.
#2
Posted 2019-February-17, 08:04
#3
Posted 2019-February-17, 10:16
In the auction you gave, I play bidding suits outside of trump, after a game force is set and trumps are set, show 1st or 2nd round control and are simply cooperating with responders desire to explore for slam below game. They do not show anything extra that what we originally promised. In this situation, bidding 4♠ simply says I have no useful outside controls to show.
Surrendering to existential truth is the beginning of enlightenment.
#4
Posted 2019-February-17, 11:40
Mr Rat said:
An example may help, suppose the auction begins (uncontested): 1H - 2D - 2S - 3S
We got to 3S, showing shape, before we found a fit. If 2S shows nothing extra then the only inference we have as to strength is that responder's 3S said something different to what 4S would have said (I believe that for most 4S would be fast arrival, so 3S is stronger than 4S. Are cues by opener now strength-showing or simply co-operating with slam investigations?
We seem to be running out of bidding space to exchange information regarding strength. I'd be interested to hear how good players solve this 'problem' (not only the specific sequence above, but the issues raised by the shape-before-strength approach in general).
2S after 2D shows nothing extra in almost any modern natural system, even the few that still play 2/1 as not game forcing. All the same, you have already exchanged plenty of information about strength, in particular responder who was willing to force to game in misfit and now shows fit at 3 level inviting a control bid. Opener will comply even with a minimum opening, unless he can bid 3nt non serious instead. If as a pair you lack necessary controls then it's going to emerge in time, you still have two entire levels of bidding to go before you commit to slam. Relax, it's a non problem.
#5
Posted 2019-February-17, 12:17
pescetom, on 2019-February-17, 11:40, said:
IMO if 2/1 is not GF, having 2S show nothing extra and not converting the auction GF is grossly inferior. I don't know any modern natural system with 2/1 not GF that advocates this. How does this work, does responder now have to 4sf with any GF and sometimes not be able to set trumps below 4M?? To me this grossly complicates thing for no apparent gain.
#6
Posted 2019-February-17, 12:29
For the 1h-2d-2s-3s auction, most expert 2/1 players have adopted 3nt after this auction as a mark time bid, either showing extra values and strong slam interest (serious 3nt) or denying them (frivolous 3nt). They do a similar thing when hearts are trump, some retaining 3nt as the artificial strength delimiter, with a 3s cue being ambiguous, while others making things more symmetric by having 3s be serious/frivolous and 3nt being a cue for spades. If partner denies strong slam interest you just sign off in game without extras yourself. After 3M major agreement, one only bypasses cue bidding and the non-serious 3nt or cue bids with the worst hands.
Most bidding theorists think 1h-2d-2s-4s played as fast arrival is inferior. They prefer to play such sequences as good diamonds and spades, no control in the other suits. The problem with fast arrival is partner is still unlimited, and you've erased your cue bidding room quite often, which kind of defeats the purpose of playing 2/1 in the first place.
As for other auctions for high reverse like 1h-2d-3c, although there are some who prefer it only shows shape and not extra strength, I personally don't think this is very playable in a wide range opening system. On this auction there is less room than in the reverse to 2s, and no serious/non-serious 3nt to disambiguate strength ranges since one has to be able to bid 3nt to play. So I think this auction is prone to missing slams when both partners have extras, but not quite enough to raise 3nt to 4nt or justify pulling 3nt to show minor fit and slam try. I play that these auctions still show extras in my partnerships.
#7
Posted 2019-February-17, 16:57
One other thing I'm struggling to find, if anyone has a moment, is the responses to 1D (if a pair have decided that 1D-2C is also GF) then where do the invitational responding hands go? We don't have a forcing (or semi-F) NT response available now, so do 10-11 counts simply jump to 2NT (natural)? 10 hcp seems a bit low to me for 2N and those with long clubs are a further complication.
EDIT: I guess you could play 1D-1N as 6-10 and 2N as 11-(bad)12. 6-10 seems a bit wide though.
Grateful for any input. N.B. I have tried Googling this but there seems a surprising lack of information (even someone's 2/1 system notes seems hard to find).
#8
Posted 2019-February-17, 17:36
It's hard to find comprehensive articles online. Books are better. Best IMO is Mike Lawrence's 2/1 software CD, nothing else (except maybe his out of print "uncontested auctions" book) gets into the nuances of 2nd and 3rd round rebids of 2/1 rebids. Other books tend to spend too much material on non 2/1-directly related stuff and don't really delve with any depth into the 2/1 auctions or forcing NT auctions that are less straightforward.
#9
Posted 2019-February-18, 17:24
"After a two-over-one response, a two-level reverse or a non-jump three-level new suit shows extra strength, but two no trump or a single raise may be based on a minimum hand.
Note: Bridge World Standard is an expert consensus based system that reflects the current state of opinion among US experts about bidding. It is used as a basis for bidding contests (most notably The Bridge World's Master Solver's Club) and often as a basis for bidding among pick-up partnerships between experts.
In addition, a simple rebid of opener's suit does not necessarily promise extra length but is a default with a minimum unbalanced hand.
After 1 ♠ - 2 ♦,
with ♠ AKxxx ♥ xx ♦ x ♣ Axxxx, you rebid 2 ♠, and,
with ♠ AKxxx ♥ Kx ♦ x ♣ AQxxx you rebid 3 ♣ showing the "high reverse" hand.
After a 2/1 response you are committed to game, so the issue becomes whether to just bid game or explore for slam. Originally, 2/1 used the above mechanisms to start to reveal to the partnership if the focus was simply toward game or possibly toward slam. The line between minimum and "extra" hands has typically been about a 16 count.
#10
Posted 2019-February-19, 10:27
Stephen Tu, on 2019-February-17, 17:36, said:
Two books that spell out 2/1 developments in some depth are "Il sistema quinta nobile a base naturale" by Franco Di Stefano and "La majeure cinqueieme" by Michel Lebel - neither of them in English, however.
#11
Posted 2019-February-19, 10:54
Mr Rat, on 2019-February-17, 16:57, said:
I think you should also evaluate the alternative 'Non-serious 3NT' (aka 'Frivolous NT') approach which Stephen and I both mentioned and which now seems to be more widespread - typically partnerships agree that it indicates minimum strength and/or lousy trumps, without denying controls.
#12
Posted 2019-February-19, 11:33
rmnka447, on 2019-February-18, 17:24, said:
"After a two-over-one response, a two-level reverse or a non-jump three-level new suit shows extra strength, but two no trump or a single raise may be based on a minimum hand.
It does, yet the only related Bridge World poll since 2001 that I can see came up with an opposite result:
420. Opener's reverse of the form one diamond -- two clubs -- two of a major . . .
A. does not promise extra values* [68]
B. does not promise extra values and denies as many as five diamonds [32]
System change: After a one-diamond opening: a two-club response is forcing to game (opener's two-of-a-major rebid does not show extra values and is ambiguous as to diamond length), a three-club response is invitational.
Please let me know if there has been any confirmation that 1H 2m 2S promises extra values - if not, maybe we should run the poll on bridgewinners
#13
Posted 2019-February-19, 12:16
Stephen Tu, on 2019-February-17, 12:17, said:
One natural system with 2/1 not GF that advocates having 2S show nothing extra is the Italian "Lungo-corto" system which was thoroughly redesigned in the mid 1980s, if you concede that as modern. It works simply with fairly natural logic: after 1H - 2C; 2S where opener's rebid does not show anything extra, responder can bid:
- 2NT or 3C (natural non-forcing)
- 3NT or 4H or 4S (fast arrival)
- 3D (4sf)
- 3H or 3S (forcing, invites control-bids).
I too would prefer 2/1 GF (and 5-card majors), but it works well enough.
#14
Posted 2019-February-19, 15:28
pescetom, on 2019-February-19, 11:33, said:
420. Opener's reverse of the form one diamond -- two clubs -- two of a major . . .
A. does not promise extra values* [68]
B. does not promise extra values and denies as many as five diamonds [32]
System change: After a one-diamond opening: a two-club response is forcing to game (opener's two-of-a-major rebid does not show extra values and is ambiguous as to diamond length), a three-club response is invitational.
Please let me know if there has been any confirmation that 1H 2m 2S promises extra values - if not, maybe we should run the poll on bridgewinners
No problem. My quote was from the "After a major opening" section of BWS. The vast majority of 2/1 auctions involve a major opener, so a 2 ♣ response to 1 ♦ is sort of a special case. In a typical session, 2/1 over a major comes up something like 4 or 5 times while 1 ♦ - 2 ♣ comes up maybe once every 2 or 3 sessions.
BWS 2017 does say a 2 ♣ response to 1 ♦ is game forcing. It further specifics what you provided that 2 of a major rebid does not promise extras and is ambiguous about ♦ length. A jump shift to 3 ♣ is invitational usually 6+ ♣ and 9-11/12.
Over a major opening, opener's reverse DOES show extras.
#15
Posted 2019-February-20, 07:48
rmnka447, on 2019-February-19, 15:28, said:
BWS 2017 does say a 2 ♣ response to 1 ♦ is game forcing. It further specifics what you provided that 2 of a major rebid does not promise extras and is ambiguous about ♦ length. A jump shift to 3 ♣ is invitational usually 6+ ♣ and 9-11/12.
Over a major opening, opener's reverse DOES show extras.
I agree that 1♦ - 2♣ is rare compared to 2/1 over a major. But I can't see why opener's reverse should show extras when he bids two majors but not when he bids two minors - if anything, the opposite would be more logical given that game in a minor requires more combined strength than game in a major. Nor does it look like BWS asked anyone to vote on what happens over a major since 2001 when 2/1 Game Force was still a minority treatment.
OK, let's run the poll on BW and see what happens
#16
Posted 2019-February-20, 08:16
pescetom, on 2019-February-20, 07:48, said:
OK, let's run the poll on BW and see what happens
2/1 GF was NOT a minority treatment in the US in 2001. Nor in 1991.
#17
Posted 2019-February-20, 09:58
Vampyr, on 2019-February-20, 08:16, said:
The Bridge World seems to have agreed in 2001 that 2/1 as an unconditional game force WAS a minority treatment at the time.
Take a look at 2017 poll 412, where an asterisk indicates the BWS2001 agreement:
412. A two-over-one response to a major-suit opening is forcing to game . . .
A. except when responder rebids his suit simply after opener has not promised extra values* [14]
B. always [86]
...
System change: After a major-suit opening: a two-over-one response is forcing to game
You can see how radically the consensus has changed since 2001, with 86% now considering it unconditionally game forcing.
Of course that is not strictly limited to the US, but it is the same base polled at different times.
#18
Posted 2019-February-20, 12:27
#19
Posted 2019-February-20, 14:13
pescetom, on 2019-February-20, 09:58, said:
Take a look at 2017 poll 412, where an asterisk indicates the BWS2001 agreement:
412. A two-over-one response to a major-suit opening is forcing to game . . .
A. except when responder rebids his suit simply after opener has not promised extra values* [14]
B. always [86]
...
System change: After a major-suit opening: a two-over-one response is forcing to game
You can see how radically the consensus has changed since 2001, with 86% now considering it unconditionally game forcing.
Of course that is not strictly limited to the US, but it is the same base polled at different times.
A above is still considered 2/1 GF. And in fact, I played that system for years and the non-GF auction came up, roughly speaking, never.