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CBS, NMF and other networks 1-way, 2-way, which way?

#1 User is offline   Al_U_Card 

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Posted 2005-September-19, 09:01

A good online pard suggested that my 2-way NMF was 2C relay to 2D (invitational or better) and 2D GF. I always took the 2-way for asking about 3 card support or 4 in the other major and a rebid in the original minor was weak. (ergo the NEW minor part of the convention)

I play CBS, as above, as well (Marty Bergen style) but this 2D GF option seems like a potentially interesting treatment. Any comments or suggestions regarding the usefulness and methods of these bids?
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#2 Guest_Jlall_*

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Posted 2005-September-19, 09:26

2 way NMF is nice because it allows you to not have to jump. You can clarify your intentions at once. Whether you play it as forcing 2D, or forcing 2D unless partner has 3 card support (then he shows it) doesn't matter much. I've played it both ways, I think it's more common to force 2D.
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#3 User is offline   mikeh 

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Posted 2005-September-19, 09:49

Playing 2 way allows for a very powerful method. Here's my variant (not that I claim to have invented it):

By UPH:

2 puppets to 2, either to play or to show most invitational hands.

2 is artificial gf. Opener makes the most descriptive bid. 2 is used for most gf hands.

2N puppets to 3. Either to play or, if followed by a bid, shows a slam try with 5+ support for partner's suit and only 4 in responder's suit.

3 level jumps: if into opener's suit: shows pure 5+ - 5+ in opener and responder's suits, with slam interest. Denies any outside A or K: allows opener to evaluate working cards/controls

If into new suit: 5-5 or better, as above

If into own suit, very good 6+ suit with slam interest.

Special sequences:

1/ 1
1N 2 invitational, 4=4 (rebid of 1N shows balanced hand, does not deny )

1/ 1
1N 2
2 2 invitational, longer


1 1
1N 2N
3 3 4, 5+, stiff or void , slam interest (typically 4=3=1=5 or 4=2=1=6)

etc
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#4 User is offline   han 

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Posted 2005-September-19, 10:27

Mikeh,

Could you please elaborate? In particular:

1) How do you play the other sequences starting with 2NT? (e.g. 1C-1S-1NT-2NT-3C-3S?)

2) What is 2C followed by a jump to 3M?

3) Did you assign any meaning to the different ways to bid 3NT?

4) What are the negative inferences for when you do bid a GF 2D (it seems that you won't have a good 6+ suit, or great support for partner's minor. Any other inferences?)
Please note: I am interested in boring, bog standard, 2/1.

- hrothgar
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#5 Guest_Jlall_*

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Posted 2005-September-19, 10:42

Another "special" sequence is 1m-1M-1N-2C(forcing 2D)-2D-3N= 5332 choice of games.
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#6 User is offline   mike777 

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Posted 2005-September-19, 11:36

yes 2c is a puppet to 2d but prefer the style where p only puppets when denying 3 card support or other 4 card major. It is too rare when you want to play 2d exactly.
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#7 User is offline   pclayton 

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Posted 2005-September-19, 11:57

Hannie, on Sep 19 2005, 08:27 AM, said:

Mikeh,

Could you please elaborate? In particular:

1) How do you play the other sequences starting with 2NT? (e.g. 1C-1S-1NT-2NT-3C-3S?)

2) What is 2C followed by a jump to 3M?

3) Did you assign any meaning to the different ways to bid 3NT?

4) What are the negative inferences for when you do bid a GF 2D (it seems that you won't have a good 6+ suit, or great support for partner's minor. Any other inferences?)

This is how I play it - in conjunction with xyz:

1) For us - 2N is only a way to get out in 3. I haven't found any particular reason to load some of the other hands onto the 2N transfer.

2 ) ....2....2...3 or our major is invitational with a 6 bagger (vs 2M = 5). 3 of the other major tends to show a 5-5 hand, but this would only be a 3 call. If you play variants of Reverse Flannery, this auction will be impacted too.

3) Yes, as Justin suggests 2 followed by 3N is an impossible auction, and thus shows a 5332 and is a choice of games.

4) Yes, 2 generally shows some sort of doubt as to final strain. It denies a great suit, and denies super support for pard's minor or a great 2nd suit.
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#8 User is offline   kfgauss 

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Posted 2005-September-19, 12:16

I prefer not to use 2NT as a relay to 3C and instead to have two ways to bid an invitational 2NT: 2C 2D 2NT, which shows 4 card support for partner's minor (or rather, is open to partner correcting to 3m) and 2NT direct, which doesn't (or rather, which isn't open to partner correcting). Then I use 3C as a signoff (hands that would bid a GF 3C are forced to start with 2D). Note that we also have the sequence 2C 2D 3m which shows a less notrumpy invite with support (basically always with 5+m).

This is very nice when partner opens 1C and it's unclear whether partner has only 3 clubs. At imps you really should be playing most 4-4 minor fits that don't make it to game in 3m, and at matchpoints probably a fair number as well. When partner opens 1D, you know he's not 4-4-3-2 (else he'd raise), so this is less necessary and perhaps gives up too much, but the help in evaluating your hand for the purposes of deciding whether to accept is nice, as is to some extent help in deciding what partscore to play (perhaps this is more important at matchpoints since you already know partner has 4 diamonds).

Andy
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#9 User is offline   inquiry 

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Posted 2005-September-19, 12:19

pclayton, on Sep 19 2005, 01:57 PM, said:

1) For us - 2N is only a way to get out in 3. I haven't found any particular reason to load some of the other hands onto the 2N transfer.

You should unload a lot of other hands not only into the 2NT auction, but into the impossible 2 auction as well. You don't have to go overboard like the scheme below, but 2NT should be harvested for something in addition to signoff in clubs.

Let's start with what I do with 2NT responses.

A direct rebid of 2NT by RESPONDER is lebehnshol, and meant to be either:

1. A signoff in clubs (pass forced 3♣ )
2. A game try with good distribution for any suit other than clubs, but less hcp than an XYZ 2♣ followed by the 3 level rebid (major raise or jump rebid)
3. Can also be used as slam tries with rebids of 3NT/4 level suits (see below!)

Item number 3 above is interesting, and shows that when playing XYZ, you have GREATLY increased your accurately describe your hands types. The seperation of different game invites via 2NT versus 2♣'s is also expanded to different game forcing hands as well using 2D, direct jumps to three/four level, 2NT -followed by 4 level rebid, and 2♣'s followed by four level bids. You can add whatever level of complexity you can remember here, here are the rules I like for "game forcing" auctions by responder (stylized for my own use of immediate 4 and 4 bid that was NOT made.
  • Direct Jumps to GAME by advancer on second turn is descriptive. If opener's rebid had been 1NT, these jumps are direct signoff. If opener had rebid 1♥ or 1♠ , responders leap to 4 of openers major shows four card support to two top honors, and five cards responders suit headed by AKJ or AKQ, no side suit singleton, no other significant values.
  • A direct jump rebid to GAME in responders major (1-1♥-1♠ -4♥, or 1♣-1♥-1♠-4♥) shows a broken seven card suit, no control in the unbid minor, and an A or K in openers major, and minimum game going values. Typical hand might be: Ax AQJxxxx xx xx (*** I use 1m-4C and 1m-4D to show seven card solid major C=H, D=S, with no side suit A or K***).
  • Delayed jumps to 4M after using 2♣ (1m-1M-1y-2♣-2-4M) shows the same kind of hand as under #2, except the side control is in opener's minor
  • Delayed jumps to 4M after using 2NT (1m-1M-1y-2NT-3♣-4M) shows the same kind of hand as under #2 , except the side control is in the 4th suit
  • Delayed jumps to four of opener's major, show the same hand types, as in number 1 above, except it conveys info about controls in one or the other suits.
  • As before, 2♣ followed by jump to four of partners major shows additional side control openers major. On 1m-1♥-1♠-2♣-2-4♠, the 4S bid shows 4-5-2-2 with two top spades, two of the top three in hearts, and A or K of opener's minor.
  • Delayed jumps via 2NT shows the same kind of hand, but with A or K of the "unbid" suit.
  • Jumps to 4♣ and 4 are splinter jumps (yes, even after 1m by opener), showing four card support for opener major (or self-splinter but ONLY if opener had rebid 1NT). This shows any great game going hand with no control in the fourth suit. Once again, it also shows minimum values for game going hands if in support of openers major.
  • Delayed direct jumps to 4 and 4♣ likewise show splinters. Again, the splinter is in support of opener's major (if he rebid one), or self-splinter. We apply PFA to these splinters, the lower the first rebid, the better the splinter. But in EACH CASE, the splinter denies a control in the fourth suit. So 1m-1x-1M-2NT-3♣-4m shows a stronger hand than the immediate (non-delayed) 4♣ rebid, while 1x-1M-2♣-2-4m shows a better hand (it started lower with 2C). You might think same logic would apply to using game forcing 2 then rebidding 4m, but no, since over 2 you have no control over openers rebid. He might jump 3NT or 3M for instance, taking the ability to use 4m as a splinter. The 2NT then 4m rebid promises a control in responders first suit (unless splinter is in that suit, in which case a control is held in the fourth suit after all), but maybe only one top card in the agreed major, while the auction through 2♣ shows control in openers first minor (unless splinter is in openers first suit, in which case it shows ACE in the fourth suit, plus one surpise extra card).
  • Direct jumps to 3M (1m-1M-1NT-3M or 1m-1x-1M-3M) shows better hands than any in the group above, but with great distribution (unsuited for the jump). With more balanced hands, unsuited for any of the above bids, simply bid game forcing 2♦-then raise the major. PFA (principle of fast arrival) applies after 2♦ then raise.

Using principle of fast arrival, even without discussing it, 1m-1M-1N-3N is weaker than 1m-1M-1N-2C-2D-3NT, 1m-1M-1N-2D-2x-3NT, 1m-1M-1N-2N-3C-3N. The first auction is game signoff, the auction with 2 was using checkback, finding no fit is signoff, the two auction using 2NT and 2C are slam invites. Both slam invites are based upon fit for openers minor using PFA principles so that the one starting 2C is the strong of the two slam invites. Below are some examples of expaned xyz auctions using these principles. This gives up on the clever little 1m-1M-1N-2C-2D-3N being 3-5-3-2 choice, but that hand is handled quite well with 2.
--Ben--

#10 User is offline   han 

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Posted 2005-September-19, 12:30

It seems that Mikeh was suggesting the following which I have not seen before but like very much:

1m-1M-1NT-2NT= either drop in clubs OR slam interest in opener's minor, exactly 4 in the major.

Then over 1m-1M-1NT-2NT-3C:

-> 3D = 4-3-(15), slam interest.
-> 3M = (42)(25), slam interest.
-> 3oM = (41)(35), slam interest.
-> 3NT= ???

It follows that you never start with 2D when you have slam interest with 5+ in partner's minor. With 5-5 jump to 3-level, with 4-5 go through 2NT.
Please note: I am interested in boring, bog standard, 2/1.

- hrothgar
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#11 User is offline   1eyedjack 

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Posted 2005-September-19, 14:34

For what it's worth my preferred method uses something along the following lines:

3D/3H/3S show 5-5 or better GF+ hands.
3C = GF+, 4441 (puppet to 3D to find shortage)
2N = GF+, 4 cards in responder's suit, 5+ in opener, + shortage OR weak Clubs (puppet to 3C)
2S = GF+, 4 cards in responder's suit, no shortage, puppet to 2N
2H = natural and weak
2D = F, any invitational hand, or a GF hand that wants control. Generally no slam interest, not much shape, interested only in major suit fits or 3N, but could be a strong balanced slam try.
2C = Weak with D, or Weak with S, or GF+ with 5+ cards in responder's first suit and no second 5 card suit (puppet to 2D).

Note that if you knock out the weak hand types, this method bucks the normal trend because it puts the invitational hands in 2D, while 2C is mainly a subset of GF hands. It so happens that arranged this way (including some GF hands in the 2S+ response) you can get to show just about any GF hand shape below the 4 level. This is not quite possible (Fibbonacci and all that) (at least not elegantly, unless I have missed something) if you put the invitational hands in 2C and start the GF hands off at 2D+.

I think this method has a certain elegance, because each GF bid shows a specific feature that is consistent throughout the subsequent bidding. Furthermore, if you have an invite, while precise distribution can be a help, any system that identifies it will get you too high on hands where it is no help, so there is little alternative to the unsophisticated min/max +/- major approach to invitational sequences. In such cases using 2D as the launching point instead of 2C does not seem to cost much. Furthermore, opener's rebids over 2D, which initially assume an invitational responder, will come in useful if responder happens to have the v strong hand type concealed in 2D.

Anyway, there you have it.
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#12 User is offline   mikeh 

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Posted 2005-September-19, 16:30

Hannie, on Sep 19 2005, 11:27 AM, said:

Mikeh,

Could you please elaborate? In particular:

1) How do you play the other sequences starting with 2NT? (e.g. 1C-1S-1NT-2NT-3C-3S?)

2) What is 2C followed by a jump to 3M?

3) Did you assign any meaning to the different ways to bid 3NT?

4) What are the negative inferences for when you do bid a GF 2D (it seems that you won't have a good 6+ suit, or great support for partner's minor. Any other inferences?)

1. Other sequences over the 2N puppet:

If opener's suit is :

a bid of one of the two side suits shows shortness, and 4=5/6 in responder's suit and

A bid of responder's suit shows 5422 and a very powerful hand: forcing to 4N or beyond

A bid of 3N shows 5422 and invitational slam values: this can be passed, and sometimes this keeps you a valuable level lower on bad-breaking hands

If opener's suit is , then over 3, a bid of 3 shows the short : all others as above.

2. 2 followed by a jump to 3 of responder's major is invitational. 6+ suit.

Note: one variant that I play in one partnership is to use an immediate jump to 3Major over 1N as invitational to 4Major, denying interest in 3N; while going through 2 shows the same invite, but allows for 3N. This means going through 2 with all one-suited major slam probes, and on balance I think this is (very slightly) inferior to the method I outlined earlier. While games are very important and more frequent then slams, in my experience, my partnerships rarely miss games in tough imp matches (making them may be more problematic :rolleyes: ), and more turns upon slam bidding in terms of actual outcome of the match, so I prefer a method that caters a little more to accurate slam bidding.

3. 2 followed by 3N: 5332, choice of games, no xx holding in any suit other than (possibly) partner's. I like to be heavy for the bid: if the game is marginal, I prefer the extra flexibility offered by the 5-3 fit, but it depends on a lot of factors and so is not a rigid rule. (Suit quality, slow values, etc.)

You can also (and should in a good partnership) discuss the inferences to be drawn between jumping to 3N over 1N and going through 2 and then bidding 3N. Certainly, going through 2 and then bidding 3N over opener's 2Major rebid can usefully be played as a balanced slam try, denying a 5 card major.

This allows opener to play 3N with a bad hand, avoiding the rare but painful 4N down one on bad breaks.

4. Negative inferences. This is one of the advantages of the method. It allows you to immediately remove certain hands from the family of hands shown via 2. This allows partner to better evaluate his holdings.

Space limits my response to this issue, but perceptive BBO readers (and are there any other kind?) will have no trouble working out the inferences. Your post already touched upon two of the important ones. Limiting the 5-5 jumps to 'picture bids' is another: with slammish 5-5 hands and weak(ish) suits and good outside cards, go through 2.

BTW, to the poster who saw no reason to load the 2N with these extra(altho rare) meanings, what is the cost? Not only is this method cost free, beyond a trifle of memory work, but what are you losing? You agree that 2N is the puppet to 3, as a signoff. So any further bid by responder is either impossible or shows a specific hand. I may be biased, but I think the suggested method is a perfet example of utilizing an otherwise impossible auction for constructve purposes in a readily learned fashion.
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#13 User is offline   Fluffy 

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Posted 2005-September-19, 19:55

2 way nmf? I don't understand the meaningofthis, if both 2 and 2 are forcing one of them rates to be not new :rolleyes:.

Roudi (french standard) uses also the 2NT transfer to 3, but it uses only 1 relay: 2, 2NT is only used for very specific invitational hands (5-5 M, 4M-6+ and 7+M) and of course to play 3.
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#14 User is offline   MickyB 

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Posted 2005-September-20, 03:49

Klinger's version uses 2N as a sign-off in clubs or an autosplinter for responder's first bid suit.
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#15 User is offline   FrancesHinden 

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Posted 2005-September-20, 06:57

There are four stages in developing responder's rebid after opener's 1NT rebid.

1. Everything natural, 2-level weak, 3-level strong. This is what beginners are taught, but very few tournament players do this.

2. 2C (in Europe) or 2-other-minor (US) as "checkback", otherwise natural, with some discussion required about what 3-level jumps mean, or the inferences available from going via the checkback. This is fairly standard online, I think (not that I actually play online, but that's another matter...)

3. Some form of 2-way checkback, as being discussed here: 2C forces 2D and covers most invitational hands; 2D is game forcing. You then need to discuss what all the new sequences you have acquired mean.

4. Transfers. Not that common, but played by a number of serious partnerships. These gives you even more potential sequences that need discussing. While I think this is theoretically best, it requires a great deal of work, because in order to take advantage you need different agreements depending on whether the response was 1D, 1H or 1S and depending on the opening bid. If you don't bother customising the transfers accordingly, I don't think it's worth playing them.

There is no "best" set of agreements, because it depends so much on what sort of hands you consider to be a 1NT rebid, and the extent to play "walsh" responses to 1C.

For example, if you never bypass a 4-card spade suit to rebid 1NT, you don't need to explore for a 4-4 spade fit.

If you allow frequent off-shape 1NT rebids, you need to take account of these in your continuations (for example, responder is not entitled to assume an 8-card fit in their 6-card major).

One hand type that's worth worrying about if you _do_ bypass the 4-card spade suit, is a weak 45 in the majors as responder.
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#16 User is offline   Al_U_Card 

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Posted 2005-September-20, 07:38

FrancesHinden, on Sep 20 2005, 07:57 AM, said:

One hand type that's worth worrying about if you _do_ bypass the 4-card spade suit, is a weak 45 in the majors as responder.

Nice resume Frances. I play CBS without the 2D GF option.

As far as the weak 4-5 and 5-4 majors holdings, I use the "cheapest" j/s to show those hands. It works well and I find it to be at least as frequent if not more than the individual WJS that they replace.
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