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2C GF Relay Response in 4cM

#1 User is offline   wank 

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Posted 2015-November-30, 00:54

Assuming you open all weak NTs with a major 1M (no strong club, no canape), does that give opener too many hand types for 1M-2C GF relay to work?
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#2 User is offline   Cyberyeti 

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Posted 2015-November-30, 03:15

I suspect not, but you'd need some multi-way rebids with re-relays to sort them out which would move it to the non-natural section.

Are you intending using the 2 relay on ALL GF hands or is there room to take a few troublesome GFs out of it ?
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#3 User is offline   nullve 

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Posted 2015-November-30, 04:13

View Postwank, on 2015-November-30, 00:54, said:

Assuming you open all weak NTs with a major 1M (no strong club, no canape), does that give opener too many hand types for 1M-2C GF relay to work?

I don't think so. I play a relay structure (RS) in a context where

1M = 19-30 Bergen points*, 5+ M, unbal.

1-2 = 3-way (nat., bal. or support)
1-2 = 4-way (nat., bal., support or IJS)

1M-2; ?:

2 = 19-21 Bergen points
...2(M=) = 3 H or 3433, inv
...2(M=) = multi-invite
...2 = GF relay
......2N+ = RS
...(...)
2 = 22-24 Bergen points (GF)
...2 = relay
......2N+ = RS
...(...)
2 = 28-30 Bergen points
...2N = GF relay
......3+ = RS+1
2N+ = 25-27 Bergen points, RS

By treating invitational hands differently, you could play

1M = 11-13 bal., 4-5 M / 19-30 Bergen points, 5+ M, unbal.

2 = 11-13 bal. / 19-21 Bergen points
...2 = GF relay
......2 = 11-13 bal. (=> 2N = relay)
......2N+ = RS
...(...)

RS (very rough outline):

2N = 4+ OM, not 5M5OM / 6+ M, one-suited
...3 = relay
......3 = 6+ M, 1-suited (=> 3 = relay)
......3+ = same as 3+ directly, but with 4+ OM instead of 4+ C
3 = 4+ D, not 5M5D
...3 = relay
......3+ = same as 3+ directly, but with 4+ D instead of 4+ C
3 = 5M5O
...3 = relay
......3 = 5M5C
......3N = 5M5D
......4+ = 5S5H
...(...)
3+ = 4+ C, not 5M5C.
More specifically:
3 = 5M4C22 or 6M4C
...3 = relay (usually W/ 2+ M unless very strong)
......3N = 5M4C22
......4+ = 6M4C
...3N = suggestion opposite 6M4C
...(...)
3 = 5M4C13 (5M044)
3N = 5M4C31
4 = 7M4C (=> 4 = relay)
4+ = 6M5C

Of course, this relay structure is in some ways less ambitious than e.g. Kerr-type relay structures, and perhaps more in the style of structures relying on Garozzo's GAR.

* In Zar Petkov's sense, where a hand contains n Bergen points iff n is its hcps plus the length of each of its two longest suits.

Added, starting 3 December 2016:
Spoiler

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#4 User is offline   Kungsgeten 

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Posted 2015-November-30, 09:26

I think it is doable, but you will probably be too high to do full relays. If I understand correctly your 1M opening is 4+ cards, not canapé and if balanced then 12-14 or 18-19? I would probably start with something fairly simple (where 2C is game forcing), and you can build from that.

One way is to make 2D a catch-all for balanced hands and 2M as a catch-all for minimum unbalanced hands.

1H--2C;
2D = 12--14 NT or 18--19 NT or semi-balanced with extras.
2H = 5+ hearts, unbalanced and minimum
2S = Natural unbalanced, extras
2NT = 6+ hearts, unbalanced extras
3m = Natural unbalanced, extras

Over 2D, 2H relays again:

1H--2C; 2D--2H;
2S = 12--14 NT
...2NT = Relay
......3m = Natural, 4-4
......3H = 5332
......3S = Natural, 4-4
......3N = 4333
2N = 18--19 NT, not 5 hearts
...3C = Relay
......3D = Natural, 4-4
......3H = 4 clubs, 4-4
......3S = Natural, 4-4
......3N = 4333
3CD = Natural, 5422 and extras
3H = Natural, 6322 and extras
3S = Natural, 5422 and extras
3N = 5332 and 18--19

You will need another relay over 1H--2C; 2H as well:

1H--2C; 2H--2S;
2N = 6+ hearts
3m = Natural
3H = 4 spades

Over 1S--2C you can do basically the same thing.
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#5 User is offline   straube 

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Posted 2015-November-30, 11:49

I don't think it's practical. We use relays after opening 10-15 5-cd majors and it's a little tough there; we're mostly +1 (lost a step) compared to standard symmetric.
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#6 User is offline   wank 

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Posted 2015-November-30, 22:51

View PostKungsgeten, on 2015-November-30, 09:26, said:

If I understand correctly your 1M opening is 4+ cards, not canapé and if balanced then 12-14 or 18-19?



that's right except that with 18-19 we effectively play 5 card majors, so 1H is either the longest suit in an unbalanced hand, a weak NT with 4 hearts, 18-19 balanced with 5 hearts or 44(41). the 4441s could be removed if that helped.
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#7 User is offline   jallerton 

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Posted 2015-December-02, 01:49

View Postwank, on 2015-November-30, 00:54, said:

Assuming you open all weak NTs with a major 1M (no strong club, no canape), does that give opener too many hand types for 1M-2C GF relay to work?


It depends what you mean by 'work'. There may be the odd sequence where you can't show the exact hand pattern below an acceptable level, but often the exact hand pattern will be irrelevant.

As I'm sure you know, there are pros and cons on relay systems. When Opener is balanced, it is less useful for Responder to know the exact shape.
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#8 User is offline   nullve 

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Posted 2015-December-02, 08:33

Just a comment on the structure I posted above:

After Opener has shown 5M4O with a bid of 3 or 3N, it's useful to have a gadget like Rodwell's Mulberry in order to set trumps and ask for key cards. But unlike in the typical structures where Mulberry is used, like Flannery or 3-suited openings, Opener's range is now very narrowly defined, but it may still not be known whether he has (5431) or extra shape, which we can take to be (5440). So instead of Mulberry I play something close to

...3[=5M4O13 (5M4O04)]-?: / ...3N[=5M4O31 (5M4O40)]-?: / ...3N[=5M4OM22]-?:

4 = minor suit slam try
...4 = no extra shape
......4 = PKC()
......4 = PKC()
......4N = undefined (but maybe "Baron" looking for a playable 7-card fit?)
......5 = to play (was hoping for extra shape)
......5 = to play (was hoping for extra shape)
...4 = extra shape
......4 = TPKC()
......4N = TPKC()
4 = major suit slam try
...4 = no extra shape
......P/4 = to play (was hoping for extra shape)
......4N = PKC()
......5 = PKC()
...4 = extra shape
......4N = PKC()
......5 = PKC()
4 = to play
4 = to play
4N = quantitative (if you like)
5 = to play
5 = to play

where

PKC(x)-?: ['PKC' = 'Parity Key Card (Blackwood)', as described here http://viewsfromtheb...-key-card.html]

4x+3 = even # of KC (=> 4x+4 = xQ ask and start of spiral scan)
4x+4 = odd # of KC, no xQ
5x = odd # of KC and the xQ

and

TPKC(x)-?: ['TPKC' = 'Truncated Parity Key Card (Blackwood)' (had to call it something)]

4x+4 = even # of KC (=> 5x+1 = xQ ask and start of spiral scan)
5x = odd # of KC (=> 5x+1 = xQ ask and start of spiral scan)

Edited 09.12.15 to include example based on deal from http://www.bridgebas...96#entry870596:


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#9 User is offline   Zelandakh 

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Posted 2015-December-03, 13:12

For full relays it is certainly too high but you might be able to get enough information not to be guessing too badly. If going the relay route I would strongly suggest the INV+ relay method for this system, as that at least allows you to split some of the hands off immediately. In the case of a 1 opening this is an obvious win for an overloaded structure.
(-: Zel :-)

Happy New Year everyone!
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#10 User is offline   Kungsgeten 

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Posted 2015-December-07, 10:11

Another, less natural, scheme. Responding 2S or higher shows extras and 5+ major.

1M--2C;
2D = Unbalanced minimum, not 6+ major
2H = 12--14 NT or 6+ major any strength
  2S = Relay
    2N = 6+M, minimum (3C relays and 3D+ as below)
    3C = 12--14 NT
      3D = Relay
        3H = 4-4 pattern (3S asks side suit)
        3S = 5332 pattern
        3N = 4333
    3D = 6+M, max, no shortness
    3H = 6+M, max, short clubs
    3S = 6+M, max, short diamonds
    3N = 6+M, max, short other major
    4CD = 6+M, max and void
    4H = 6+ major, max and void other major
2S = 4+ clubs
2N = 4(+) cards in other major
  3C = Relay
    3D = No shortness
    3H = Short clubs
    3S = Short diamonds
3C = 4 diamonds and shortness
3D = 4 diamonds no shortness
3H = 5+ diamonds, clubs
3S = 5+ diamonds, short other major
3N = 5+ diamonds, void clubs
4C = 5+ diamonds, void other major


Over 2D responder can relay and opener responds as 2S+ above. Over 2S
opener relays and respones as 3C+ above. Over 3C opener can relay to
find out about shortness (as 3H and 3S above). 5-5 majors is
problematic, which in my experience they always are when designing
relay structures :P

12--14 NT end up high, but you find out about the most important
aspects (min/max, hand type and shortness). 6-4 hands and 7+ suits are
problematic.
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#11 User is offline   nullve 

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Posted 2015-December-07, 13:08

View PostKungsgeten, on 2015-December-07, 10:11, said:

5-5 majors is problematic, which in my experience they always are when designing relay structures :P

One possibility, based on my structure above:

...3(5S5O)-3(relay); ?:

(...)
4 = 5512 or 5503
...4 = relay
......4 = 5512 (=> 4N = PKC(); 5 = PKC())
......4 = 5503 (=> 4N = PKC(); 5 = PKC())
4 = 5521 (=> 4N = PKC(); 5 = PKC())
4 = 5530 (=> 4N = PKC(); 5 = PKC())

Similarly with 6M4OM:

...2N(6+M4+OM, not 5S5H / 6+ M, 1-suited)-3(relay); 3(5M4OM22 or 6M4OM)-3(relay); ?:

(...)
4 = 6M4OM12 or 6M4OM03
...4 = relay
......4 = 6M4OM12 (=> 4N = PKC(); 5 = PKC())
......4 = 6M4OM03 (=> 4N = PKC(); 5 = PKC())
4 = 6M4OM21 (=> 4N = PKC(); 5 = PKC())
4 = 6M4OM30 (=> 4N = PKC(); 5 = PKC())

Edited to include example based on hands from http://www.bridgebas...ge__pid__870494, but with South as dealer instead of North:



(Of course, North could have jumped to 7 over 5N.)
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#12 User is offline   nullve 

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Posted 2015-December-08, 07:33

View PostKungsgeten, on 2015-December-07, 10:11, said:

7+ suits are problematic.

My one-suited structure (based on the above) is effectively +5(!!), sometimes +4(!), Symmetric Relay, but it works reasonably well partly because Responder has had plenty opportunity to revert to natural on unbalanced hands without tolerance for Opener's major. The structure is close to:

...3(6+ M, 1-suited)-3(relay, usually 2+ M); ?:

3 = SPL C or 6M(32)2 [the potentially misfitting "low shortage" oppposite a hand with real clubs is included in the first step, unlike in Symmetric Relay]
...3N = relay
......4 = 6M(32)2
.........4 = relay
............4 = 6M232 (=> 4M+1 = RKC(M))
............4 = 6M322 (=> 4N(M=) = PKC(); 4N(M=) = RKC())
......4+ = same as 4+ directly, but with SPL C instead of SPL OM
3N = SPL D
...4 = relay
......4+ = same as 4+ directly, but with SPL D instead of SPL OM
4 = 6M223 or 7M222
...4 = relay
......4 = 6M223 (=> 4M+1 = RKC(M))
......4 = 7M222 (=> 4N(M=) = PKC(); 4N(M=) = RKC())
4+ = SPL OM [i.e. "high shortage" instead of +4 Symmetric Relay's "low shortage"]
Specifically:
4 = 6M1OM33 (=> 4M+1 = RKC(M))
4 = 7M1OM23 (=> 4M+1 = RKC(M))
4 = 7M1OM32 (=> 4N(M=) = PKC(); 4N(M=) = RKC())
4N = 7M0OM33 (=> 5(M=) = TPKC(); 5(M=) = PKC())
(...)
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