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1M-2C Artificial GF Structure Help Please!

#1 User is offline   giga4u 

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Posted 2017-August-15, 06:40

Hi All,

Looking for tips and suggestions regarding the 1M-2 as any artificial GF. This is in line with a 5 card major, strong NT, transfer responses over 1 system.

The basic structure over 1 looks something like this:

1NT = 6-11 (12), NF
2 = Artificial GF
2 = Good raise to 2M, so a 9-11pt 3 card raise, or a 8-10pt 4 card raise , no stiff
2 = weak raise, say 4-8
2 = 8-11 BOTH MINORS (5+-5+) [*Or play this as the mixed raise, and therefore 3 as pre-emptive]
2NT = 4+ card support, inv+
3 = invitational with 6+ clubs
3 = invitational with 6+ diamonds
3 = mixed raise, 7-9 pts, 4 card support [*or pre-emptive]

Responses to 1 is similar to the above with 2 showing hearts, 2 as good raise to 2

My main concerns are:

  • Point 1: After 1M-2, what are the continuations by opener? 2 to show various MINIMUM hands or various GOOD hands? 2M and 2NT swap meanings? I hate the idea of bidding 2NT with 5332 potentially wrong siding the contract
  • Point 2: How does responder show a 1 suited minor GF, or both minors GF? how does he/she get their hand across or is point 3 (below) important)? Should I alter any of the above structure i.e. 1M-3/3 as a 1 suiter GF? Could 1-2be used as a good raise to 2 OR GF both minors?
  • Point 3: Is it more important finding out what opener's hand type is like? or responder's hand type? maybe responder just uses bids/some sort of relay structure to find out about opener so nothing is revealed about responder's hand?


Obviously this is for 2 or 3 regular partnerships. A relay structure would be very informative, however I'm not sure 2 of my partners would want this if it's too complicated... I'm all ears for this though :)

I'm sorry if I've put too much questions into this post! Any other suggestions/comments regarding the basic structure will be useful!

Thanks in advance.
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#2 User is offline   Kungsgeten 

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Posted 2017-August-15, 08:04

What hand types are included in 1M? Can it be balanced (5332), and if so, what strength?

You could have a look at the Ambra system: http://www.eclipse.c...a5046/ambra.htm

If I remember correctly, they use the 2D rebid to show any minimum without 4+ cards in the other major, while 2H shows 4+ cards in the other major and 2S or higher shows shape and extras.
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#3 User is offline   The_Badger 

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Posted 2017-August-15, 10:33

hi giga4u. Welcome to the forum :)

My experience of a 2 universal game force by responder is that if you are going to employ a relay system, you should not have any other bids that are GF too, such as (in Point 2) - 1M-3/3. The idea of a relay system is to save space as well as describing a hand in much detail as possible.

Personally I am very dubious as having 1NT as non forcing with such a large range. Also, on first impression, I am not quite sure where you are at with having a two-way 2 constructive raise, a 2NT invitational raise and a 3 mixed raise available to describe similar type hands. These need to be more clearly defined I feel so opener has a better picture of your hand.

I am firm believer - my opinion only - that it's usually easier for the stronger hand to take a lead in the auction. That's easy after a Precision 1 opening, for example, because if responder has a stronger hand than opener he knows automatically that the partnership is in the slam zone.

Obviously using a 2GF with a standard opening bid, neither player will know initially (except a minimum opener) which hand is the stronger.
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#4 User is offline   awm 

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Posted 2017-August-15, 11:05

Here's our relay structure over 1S-2C for what it's worth:

2D: clubs or one suited without shortness
... 2H relay and 2S one suited, 2N+ like below
2H: diamonds
... 2S relays and 2N+ like below
2S: one suited with some shortness
... 2N asks shortage
2N: 5-5 or more majors
3C: 4 hearts high shortage
3D: 5422 or 5440 or 7411
3H: 5431
3S: 6421
3N: 6430
4C+: 7420
Adam W. Meyerson
a.k.a. Appeal Without Merit
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#5 User is offline   mikestar13 

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Posted 2017-August-15, 15:45

The following links have some useful ideas about the 2 response:

http://bridgewinners...ebulous-2c-bid/
http://bridgewinners...us-2c-response/
http://bridgewinners...-to-1m-opening/

You will need to modify these structures a bit as your 2 can include GF with long diamonds. Perhaps also the GF long hearts type after a 1 opening--but you might try 2 transfer to hearts, <11 or GF., or perhaps just GF with the weaker heart hands bidding 1NT.
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#6 User is offline   giga4u 

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Posted 2017-August-15, 15:46

View PostKungsgeten, on 2017-August-15, 08:04, said:

What hand types are included in 1M? Can it be balanced (5332), and if so, what strength?

You could have a look at the Ambra system: http://www.eclipse.c...a5046/ambra.htm

If I remember correctly, they use the 2D rebid to show any minimum without 4+ cards in the other major, while 2H shows 4+ cards in the other major and 2S or higher shows shape and extras.


Yes it can be 5332 and therefore 11-13 or 17-19 (Our NT range is 14-16)

Thanks for that - will have a look. Is there a simple structure over this?
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#7 User is offline   ynhhyjb 

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Posted 2017-August-16, 21:19

golady contract:
1 2
2:5+,2nt asks shortage
2:4,2nt asks shortage
2:4+,2nt asks shortage
2nt:4,3,asks shortage
3:5+,3,asks shortage
3:4504
3:0544
3nt:4540
3:5+,minimum

1 2
2:4+,2nt asks shortage
2:5+,2nt asks shortage
2:4+,2nt asks shortage
2nt:4,3 asks shortage
3:5+,3 asks shortage
3:5404
3:5044
3nt:5440
3:5+,minimum
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#8 User is offline   nullve 

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Posted 2017-August-17, 12:55

To those who have experience with a shape first symmetric relay structure (such as awm's) over 1M-2 when 1M has a standard wide range:

A) How do you feel about the information leakage when both hands are fairly minimal but Responder continues to relay for shape just in case Opener is at the top of his range?

Ex.:

Opener: 12 hcp, 5143
Responder: 13 hcp, 3424
Bidding:

11-22
23-24
35-?,

1 "10-21", 5+ S
2 GF relay
3 4+ D
4 relay
5 5143

using awm's structure.

B) Does the loss of a step compared with standard symmetric become a big problem? (I know awm doesn't think so when 1M has a Precision-like range.)
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#9 User is offline   Kungsgeten 

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Posted 2017-August-18, 00:18

View Postgiga4u, on 2017-August-15, 15:46, said:

Yes it can be 5332 and therefore 11-13 or 17-19 (Our NT range is 14-16)

Thanks for that - will have a look. Is there a simple structure over this?


Relays like these are usually coded and highly artificial, but follow a set of logic, patterns and rules. If you understand and learn the theory of the construction, it is pretty simple - but if you forget it can get out of hand (compared to natural bidding where you bid what you have).
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#10 User is offline   awm 

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Posted 2017-August-18, 10:45

We can always blast games rather than relay. We also have ways to show a game force raise that has slam interest only opposite a real max. So the relays only get a lot of use when we are slam interested or have serious doubts about the strain for game.

Another point is that in this structure, opener only bids Notrump with extra shape (helps some on siding issues).

We do use 1H-1NT as relay (saving a step and also right siding notrump) which is why I gave only the 1S auction here.
Adam W. Meyerson
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#11 User is offline   foobar 

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Posted 2017-August-18, 11:41

View Postawm, on 2017-August-18, 10:45, said:

We can always blast games rather than relay. We also have ways to show a game force raise that has slam interest only opposite a real max. So the relays only get a lot of use when we are slam interested or have serious doubts about the strain for game.

Another point is that in this structure, opener only bids Notrump with extra shape (helps some on siding issues).

We do use 1H-1NT as relay (saving a step and also right siding notrump) which is why I gave only the 1S auction here.


Can we have more details please :D? My guess it that 1H - 1N as a relay presumably uses some form of Kaplan inversion? Also, it would be interesting to know about the other 2-level responses over 1M.
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#12 User is offline   awm 

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Posted 2017-August-18, 12:14

Steps basically:

1H-1S = at most bad 12, no fit, any # of spades
1H-1NT = GF or 12-13 with 5+ spades
1H-2C = 12-13 0-4 spades
1H-2D = 10 to bad 12 with 3+H
1H-2H = 5-9 natural
1H-2S, 1H-3m = 0-9 hcp 6+ suit natural
1H-2NT = mixed raise
1H-3H = weak
Higher = splinters

1H-1S:
... 1NT = 3-4 spades
... 2m = natural, 2C can be 2533
... 2H = natural 11-bad 15 (weaker opens 2H)
... 2S = 5H+6m not min
... 2NT = 5S+6H
... 3m = 6/5 not min
... 3H = 7 hearts not min

1H-1S-1NT:
Pass = less than 11, 3145 or similar
2C = asking, 4+ spade 8+ hcp
2D = less than 11 5+D usually 3154 or 5-5 minors
2H = doubleton 8-12 not four spades
2S = to play
2NT = 11-12 31(45) or similar
3m = 6+ suit 10-11 hcp

1H-1S-1N-2C:
... 2D = 3S-5H
... 2H = 3S-6H
... 2S+ = 4S, past 2S shows extras and shape

1H-1NT... immediate relay breaks show 5S (i.e. 1H-1N-2C-2H five spades doubleton heart 12-13). Also note that 2H+ rebid by opener is always GF

1H-2C:
2D = not four spades, if max not some shapes
2H = four spades 9-11
2S = four spades 12+
2nt = 6+ heart 11+
3m = 5/5 or more 11+
3H = short spades 51(43) 12+

Usually responders next bid after 1H-2C-2D is natural NF except a jump to 3H which is a min GF raise 12-13.

After 1S we have 1NT "up to a bad 12, semi force" and 2D/2H are like 2C/2D above.
Adam W. Meyerson
a.k.a. Appeal Without Merit
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#13 User is offline   Zelandakh 

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Posted 2017-August-19, 04:46

Over 1 I strongly prefer initiating relays with 1 rather than 2.

1
==
1 = INV+ relay
... - 1NT = min with <4 spades (now 2 is your GF relay with fewer hand types to worry about)
... - 2 = 4+ spades (now 2 is the GF relay)
... - 2+ = extras with <4 spades, FG
1NT = weak, 4+ spades
2 = weak, 4+ clubs, usually <4 spades
2 = weak, 5+ diamonds, usually no other suit
2+ = various raises
--

My preference is to use a similar structure over 1 as well but as this makes the primary GF relay 2 it is less clear which is better.

If you are really set on the FNT approach in combination with relays over 1 then Adam's suggestion (using 1 rather than 1NT) is the way to go. As always, it is not the relay hands that you need to focus on in the system design - designing a relay structure is easy - but everything else!
(-: Zel :-)
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#14 User is offline   straube 

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Posted 2017-August-23, 09:10

View Postawm, on 2017-August-18, 12:14, said:

Steps basically:

1H-1S = at most bad 12, no fit, any # of spades
1H-1NT = GF or 12-13 with 5+ spades
1H-2C = 12-13 0-4 spades
1H-2D = 10 to bad 12 with 3+H
1H-2H = 5-9 natural
1H-2S, 1H-3m = 0-9 hcp 6+ suit natural
1H-2NT = mixed raise
1H-3H = weak
Higher = splinters



If it goes 1H-1S* (2C) there isn't a support double here as responder hasn't shown spades. What have you found works best for the double here? Double could show spades anyway. Let's say it promises 3 spades and responder has 3-1-5-4. One could land in a 5-1 or 3-3 fit. Or let's say dbl promises 4 spades; then one might miss a 5-3 spade fit.

Or if 1H-1S* (3C) it seems like a 5-4 spade fit could be missed here as it is risky for opener to double with spades unless extras.
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#15 User is offline   awm 

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Posted 2017-August-23, 10:55

We play double as takeout, much like the standard 1S-1nt auction. Certainly it is possible to have trouble competing after a three level preempt, although these hands are not always easy in standard either (if opener bids 3s without extras you can get too high; otherwise you can occasionally fail to compete).

On the other hand, concealing responders spades can win in many ways too (opponents can bid 2S and get doubled, or end up on a guess on lead, and it's also easy to deal with less than GF 4S-6m hands).
Adam W. Meyerson
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#16 User is offline   straube 

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Posted 2017-August-25, 16:24

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#17 User is offline   foobar 

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Posted 2017-August-25, 16:45

View Poststraube, on 2017-August-23, 09:10, said:

If it goes 1H-1S* (2C) there isn't a support double here as responder hasn't shown spades. What have you found works best for the double here? Double could show spades anyway. Let's say it promises 3 spades and responder has 3-1-5-4. One could land in a 5-1 or 3-3 fit. Or let's say dbl promises 4 spades; then one might miss a 5-3 spade fit.

Or if 1H-1S* (3C) it seems like a 5-4 spade fit could be missed here as it is risky for opener to double with spades unless extras.

The 1 - 1 sequences are probably similar to Kaplan inversion, but it's difficult to compare since 1 - 1N says nothing about spades. This thread may have some discussion about competitive situations over KI: http://bridgewinners...rsiongranville/
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#18 User is offline   straube 

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Posted 2017-August-25, 17:29

I guess I'm concerned that after 1H-1S (2m) opener has only one way of "showing" spades while most others in the room would have two. I think Adam doesn't like responding a semiforcing NT with an invitational hand and losing out on game when opener passes with a 5332. The other motive seems to be saving a step (1N vs 2C) for relays.

I'd thought "well. One could respond 1S natural OR certain invitational hands that don't have spades". In this way opener could safely raise spades and then responder could correct. But this still leaves 2C as the GF relay and it muddies things.

I quite like Adam's continuations after 1H-1S natural and he's using 2C as relay for spade openings. Why not just play forcing NT then to get to those 5332 games? Responder has the 2S rebid to sort out 4 fro 5 cd minor suit raises anyway... as in 1H-1N, 2m-2S
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#19 User is offline   nullve 

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Posted 2017-August-26, 09:17

View Postgiga4u, on 2017-August-15, 06:40, said:

Hi All,

Looking for tips and suggestions regarding the 1M-2 as any artificial GF. This is in line with a 5 card major, strong NT, transfer responses over 1 system.

The 1M range may matter a lot.

The point I was trying to make in A) in my previous post is that if the range is very wide (like "10-21") and a shape first relay structure is used, then Responder might keep relaying just in case Opener has, say, "19-21" rather than "10-12". (The alternative seems to be to admit that the relay structure doesn't handle "19-21" hands very well.) This leads to potentially harmful information leakage on bread and butter hands, often with Opener declaring 4M, that can easily avoided by using e.g. an Ambra-style structure instead.

View Postawm, on 2017-August-18, 10:45, said:

We can always blast games rather than relay. We also have ways to show a game force raise that has slam interest only opposite a real max. So the relays only get a lot of use when we are slam interested or have serious doubts about the strain for game..

Not sure if this was partly a comment to my previous post, but...

We can always blast games rather than relay.

Still true if the range is "10-21" instead of "10-15"?

We also have ways to show a game force raise that has slam interest only opposite a real max

Via early relay breaks, right? How would the analogous bidding typically go with

Opener: 12 hcp, 5143
Responder: 14 hcp, 3424,

assuming the 1 range is "10-21"?

So the relays only get a lot of use when we are slam interested or have serious doubts about the strain for game..

But with enough to force to game opposite "10-21", Responder can really never rule out slam until he learns more about Opener's strength.
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