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Gerber?

#1 User is offline   smerriman 

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Posted 2021-November-01, 16:45



I posted South's hand as an IMPs bidding problem on BridgeWinners. As I didn't want to influence the results, all I stated was strong no trump, 2 range ask, 3 puppet, all other responses standard.

So far there are 26 votes for 6NT, and a couple each for 2 and 3.

If partner is missing the AK of hearts, we shrug our shoulders; bad luck but slam was worth bidding.

When partner upgraded to a 1NT opening and we're missing two aces, and we had a bid to detect that, it feels like maybe we made a mistake.

The only downside of 4 appears to be that the opening leader will get a slight negative inference due to the lack of a lead directing double of 4. Does this cost more in the long run than avoiding slam here?
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#2 User is offline   LBengtsson 

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Posted 2021-November-01, 21:51

The poll on bridgewinners says it all...

who uses gerber? 33-34 in no trump contract for small slam. what it does not say on the ingredient tin is that with 33 or 34 points you will make 6NT also. north has AK K AJ and east leads QJ10 and his partner has A. not just missing AK 6NT will not make.
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#3 User is offline   smerriman 

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Posted 2021-November-01, 21:59

View PostLBengtsson, on 2021-November-01, 21:51, said:

who uses gerber? 33-34 in no trump contract for small slam. what it does not say on the ingredient tin is that with 33 or 34 points you will make 6NT also. north has AK K AJ and east leads QJ10 and his partner has A. not just missing AK 6NT will not make.

I'm not following what you're saying. Sure, 6NT won't make always.. but not sure what that has to do with my question.
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#4 User is offline   AL78 

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Posted 2021-November-02, 03:01

I think 6NT is a reasonable punt. 32-34 HCP combined it will make more often than it doesn't. If your partner has a habit of upgrading 14 counts it may be prudent to bit a quantitative 4NT with the risk they pass with a suitable 16 count. It is a little unlucky the eight HCP missing are exactly two aces, on many other hands with 32 HCP combined it will either be cold or there will be decent chances.
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#5 User is offline   Douglas43 

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Posted 2021-November-02, 03:07

It's a risk you take with upgrades and to a lesser extent downgrades (and I do upgrade and downgrade fairly freely)
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#6 User is offline   LBengtsson 

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Posted 2021-November-02, 03:30

View Postsmerriman, on 2021-November-01, 21:59, said:

I'm not following what you're saying. Sure, 6NT won't make always.. but not sure what that has to do with my question.


yes, gerber, will save auction reaching 6NT, but as I said "who uses gerber?" not one player when you posted on BW has made suggestion to use gerber on this auction, so that says to me that gerber is a convention that has disappeared from modern bidding. maybe some English players still use Gerber: many, I guess here, use 4 as transfer with slam interest instead of.
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#7 User is offline   P_Marlowe 

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Posted 2021-November-02, 04:04

The more interesting question may have been, who would upgrade the North hand?
With kind regards
Uwe Gebhardt (P_Marlowe)
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#8 User is offline   TMorris 

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Posted 2021-November-02, 04:20

Using Gerber here is evidence that your strong NT range is not 15-17
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#9 User is offline   DavidKok 

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Posted 2021-November-02, 04:49

Well, at least I'm consistent with my answer over at Bridgewinners. I never dreamed that 6X might go down, but I would have found out using the slow method. Incidentally my partnership plays 14-16 NT but we would always open 1 with the North hand.

I think the claim that just jumping to 6NT is not optimal is very defensible. There are lots of things that might be important on this particular deal, though I was more focused on strain than on aces. However, you seem to be making the much stronger claim that Gerber would not only have avoided this failing slam, but in fact it would have been the right call by responder. I strongly disagree - Gerber will help you only in the specific case that partner upgraded a 14-count with a single ace, and not help you opposite any other hand. As others have pointed out on bridgewinners a lead-directing double, or lead-directing absence of a double, is likely to harm you more percentage wise than catering to the slim chance of the upgraded single-ace 14-counts.
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#10 User is offline   P_Marlowe 

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Posted 2021-November-02, 04:50

Hi,

we play

4C as 55 majors
4D / 4H as Texas

Alternative, you could play 4C / 4D as Texas.
The additional step enables the NT opener to show fitting values.

Both variants are not uncommon, and my explain, why no one mentioned
4C Gerber.

With kind regards
Marlowe
With kind regards
Uwe Gebhardt (P_Marlowe)
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#11 User is offline   P_Marlowe 

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Posted 2021-November-02, 04:53

View PostDavidKok, on 2021-November-02, 04:49, said:

Well, at least I'm consistent with my answer over at Bridgewinners. I never dreamed that 6X might go down, but I would have found out using the slow method. Incidentally my partnership plays 14-16 NT but we would always open 1 with the North hand.

I think the claim that just jumping to 6NT is not optimal is very defensible. There are lots of things that might be important on this particular deal, though I was more focused on strain than on aces. However, you seem to be making the much stronger claim that Gerber would not only have avoided this failing slam, but in fact it would have been the right call by responder. I strongly disagree - Gerber will help you only in the specific case that partner upgraded a 14-count with a single ace, and not help you opposite any other hand. As others have pointed out on bridgewinners a lead-directing double, or lead-directing absence of a double, is likely to harm you more percentage wise than catering to the slim chance of the upgraded single-ace 14-counts.

Yes, if you regular open 1NT with a 5 card major suit, it is sensible to play some sort of puppet stayman as well.
Keeps the auction lower as well.
With kind regards
Uwe Gebhardt (P_Marlowe)
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#12 User is offline   DavidKok 

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Posted 2021-November-02, 04:56

I also noticed that you wrote "If partner is missing the AK of hearts (and they're led; you may still have 12 tricks if not), then you shrug your shoulders and move on; bad luck but 6nt was still right." over at Bridgewinners. I think this is actually a very typical mistake players often make. This argument is true if you had no way to find out, or if you insist that the opponents are odds-on to not cash two heart tricks if they have them provided you don't tell them.

A (non-existent, theoretical) bidding system would bid the games and slams that make and avoid the ones that don't. Temporarily setting aside considerations of information leakage, if you have ways to find out whether your game/slam is going to make/fail, it is better to find out rather than play the odds (even if the odds are very good). Arguments along the lines of "what is the chance that with 32 combined points we are off exactly AK in one suit? Therefore 6NT was a good bid" are correct only if you had no safe way to find out during the bidding. If you jump the auction by five levels you lose right to use this argument, immediately.

Back to the information leakage: that is a much more complicated and nuanced topic, and provides a good argument for just blasting 6NT. But the argument is "I figured that, given that we were off two quick tricks, the opponents were not likely to find them and we have 12 tricks without being forced to hand the opponents their two. Therefore, on balance, the lack of leaked information improves the odds of making 6NT by so much that I'm willing to take the risk of landing in a hopeless contract some small avoidable fraction of the time."
I personally think that statement does clearly not apply on the hand shown - the chance that you have 12 tricks in only three suits is abysmal (although, on reflection, maybe the conditional chance "we have 12 quick tricks outside hearts conditional on being off the AK" might be quite high), so you will have to bring the opponents their two aces/ace-king in any suit. But at least this point is somewhat debatable - the first is just mistaken.
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#13 User is offline   Douglas43 

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Posted 2021-November-02, 08:13

View PostP_Marlowe, on 2021-November-02, 04:04, said:

The more interesting question may have been, who would upgrade the North hand?


I would if playing 15-17. It's got three 10s and the spade suit is four of top five cards.
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#14 User is offline   mw64ahw 

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Posted 2021-November-02, 09:27

View PostDouglas43, on 2021-November-02, 08:13, said:

I would if playing 15-17. It's got three 10s and the spade suit is four of top five cards.

Mildly positive in terms of 'Quacks', but Jx is a negative and I don't upgrade without an MLT<=6.5
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#15 User is offline   DavidKok 

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Posted 2021-November-02, 09:34

Depending on your system there's no need to misdescribe upgrade the hand. You have the boss suit so interference is not a problem, and if partner has a way to show 10-11 balanced over 1 you won't miss 3NT. If anything, opening 1NT makes you miss 4.

Sticking to MLT with the interior sequence in spades and both red 10s seems a bit too dogmatic. I think the hand is well worth a 15-17 NT opening, but a 1 opening is even better.
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#16 User is online   Winstonm 

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Posted 2021-November-02, 12:52

View PostDavidKok, on 2021-November-02, 09:34, said:

Depending on your system there's no need to misdescribe upgrade the hand. You have the boss suit so interference is not a problem, and if partner has a way to show 10-11 balanced over 1 you won't miss 3NT. If anything, opening 1NT makes you miss 4.

Sticking to MLT with the interior sequence in spades and both red 10s seems a bit too dogmatic. I think the hand is well worth a 15-17 NT opening, but a 1 opening is even better.

What is your rebid if partner bids 1NT?
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#17 User is offline   smerriman 

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Posted 2021-November-02, 13:14

View PostDavidKok, on 2021-November-02, 04:49, said:

However, you seem to be making the much stronger claim that Gerber would not only have avoided this failing slam, but in fact it would have been the right call by responder. I strongly disagree - Gerber will help you only in the specific case that partner upgraded a 14-count with a single ace, and not help you opposite any other hand. As others have pointed out on bridgewinners a lead-directing double, or lead-directing absence of a double, is likely to harm you more percentage wise than catering to the slim chance of the upgraded single-ace 14-counts.

Almost. I was saying Gerber would avoid this, and *asking* whether it would have been the right call :) One person on BridgeWinners mentioned what additional information the leader would have, but not whether this would cost more long term. I'm guessing it does, but was posing that question here as I wasn't really sure how to quantify it.

View PostDavidKok, on 2021-November-02, 04:56, said:

Therefore 6NT was a good bid" are correct only if you had no safe way to find out during the bidding. If you jump the auction by five levels you lose right to use this argument, immediately.

Agreed with this. To be honest, I thought all of the lower level bids over 1NT are pretty much set in stone these days other than a few minor variations, so wasn't aware there was a way of going slower. How would you bid these hands (and generally ones missing AK too) in your system?
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#18 User is offline   mycroft 

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Posted 2021-November-02, 13:53

I hate Gerber, but if you're likely to "upgrade" a lot, then quantitative bids either have to take that into account, or deal with a very wide range. Which, for slam, is - unfortunate. Or you can use G to ensure you're not off two Aces in your "33"-35HCP. If you do, I'm not sure what hands you're bidding 4NT on, so you could turn that into a "quantitative" "pass if you don't have two aces" call. But then you wouldn't need Gerber again, so you would need 4NT regularly quantitative, and so on.

So for the safety you get by "checking on the way", you get the possibility of the lead-director or the sacrifice-director, plus partner is less comfortable when the auction gets busy (do you have the "real" Gerber hand, where you can see 12 tricks if I have enough aces, or do you have "we have 33 high unless you pushed - again?).

Plus, how often is the 8 missing A,A? How often is it AK suited and a jack (or AQ offside)? How often can they find it if it is? Those also apply, in addition to "how many 14s are in your 15-17 NT?", in your consideration.

Frankly, if you're opening enough 14s that you think you need to use Gerber with a random 18-count, but you're describing your openings as "15-17", I think there's a more important issue than the odd bad slam. But I know, all the "real bridge players" should know about it, so it's not a problem, right?
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#19 User is offline   nige1 

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Posted 2021-November-02, 14:56

View Postmycroft, on 2021-November-02, 13:53, said:

I hate Gerber, but if you're likely to "upgrade" a lot, then quantitative bids either have to take that into account, or deal with a very wide range. Which, for slam, is - unfortunate. Or you can use G to ensure you're not off two Aces in your "33"-35HCP. If you do, I'm not sure what hands you're bidding 4NT on, so you could turn that into a "quantitative" "pass if you don't have two aces" call. But then you wouldn't need Gerber again, so you would need 4NT regularly quantitative, and so on.

So for the safety you get by "checking on the way", you get the possibility of the lead-director or the sacrifice-director, plus partner is less comfortable when the auction gets busy (do you have the "real" Gerber hand, where you can see 12 tricks if I have enough aces, or do you have "we have 33 high unless you pushed - again?).

Plus, how often is the 8 missing A,A? How often is it AK suited and a jack (or AQ offside)? How often can they find it if it is? Those also apply, in addition to "how many 14s are in your 15-17 NT?", in your consideration.

Frankly, if you're opening enough 14s that you think you need to use Gerber with a random 18-count, but you're describing your openings as "15-17", I think there's a more important issue than the odd bad slam. But I know, all the "real bridge players" should know about it, so it's not a problem, right?
Gerber seems a sensible safety-play :)
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#20 User is offline   DavidKok 

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Posted 2021-November-03, 04:03

View PostWinstonm, on 2021-November-02, 12:52, said:

What is your rebid if partner bids 1NT?
My 1NT is 6-9 with the occasional soft 10, and denies three spades. So I have an easy pass. The 10-11 (semi)balanced hands without spade support go through 2 (artificial) in my system. In some sense this is a chicken-and-the-egg situation: it is a bit unfair of me to spring this on people playing vanilla 2/1, where you have a serious problem over a SF 1NT (but not over a F 1NT, you systematically rebid 2 or 2 depending on partnership agreement). However, we play this artificial 2 precisely to ensure we can always show our major without rebid problems.

View Postsmerriman, on 2021-November-02, 13:14, said:

Almost. I was saying Gerber would avoid this, and *asking* whether it would have been the right call :) One person on BridgeWinners mentioned what additional information the leader would have, but not whether this would cost more long term. I'm guessing it does, but was posing that question here as I wasn't really sure how to quantify it.
Ah, my mistake. I think bidding Gerber is probably slightly better on balance than blasting to 6NT (I said the opposite earlier but changed my mind), if partner is likely to upgrade 14-counts. But personally I think the point is moot since I prefer a different approach altogether.

View Postsmerriman, on 2021-November-02, 13:14, said:

Agreed with this. To be honest, I thought all of the lower level bids over 1NT are pretty much set in stone these days other than a few minor variations, so wasn't aware there was a way of going slower. How would you bid these hands (and generally ones missing AK too) in your system?
I think there is a very definite 'expert standard', with a few slight variations. I don't like the standard at all, but good luck convincing people to give up Stayman. However, the followups are a complete mess, and they are different for every partnership (and often not discussed). For what it's worth, I think the standard response structures are (note: the multiple options mean that the partnership has to pick one meaning and stick with it, not that you have multi-way bids):
  • 2: Stayman. Usually either Garbage (can contain a weak 5-4 majors or weak three-suiter with short clubs), Crawling (same but can also contain weak 4-4 majors) or constructive (always shows at least an invitational hand).
  • 2: 5(+) hearts. May contain 4 spades if not playing Smolen.
  • 2: 5(+) spades. May contain 4 hearts if not playing Smolen. May always contain 5 hearts.
  • 2: Range ask, also used to show a weak hand with clubs.
  • 2NT: Four options: 1) transfer to diamonds, 2) puppet stayman, 3) natural NF invitational, 4) GF balanced slam try ('4NT but 2 levels lower'), although this is somewhat of a duplicate of the 2 range ask.
  • 3: Two options: 1) puppet stayman (note: there are about 3-4 different flavours of puppet stayman that see play with different continuations. I play a very simple one but like the Lall version), 2) transfer to diamonds.
  • 3: - (I don't know of a standard use for this bid. I think people tend to dump the Achilles' heel of their agreement here - something like 5-5 majors, exactly invitational values).
  • 3: 3=1=(4-5), GF.
  • 3: 1=3=(4-5), GF.
  • 3NT: To play, not descriptive.
  • 4-level: Either Gerber and 1-under transfers denying slam interest (Texas transfers), or 2-under transfers showing mild slam interest (South African Texas transfers).

As I said the continuations are a crapshoot. For example, in my regular partnership the direct jump to 3 shows 5-5(+) majors and a GF, the hand with exactly invitational values starts with 2 and rebids 3 if partner responds 2 (there is no problem over a 2M response, and over a 2NT response showing a 6-card minor we are in serious trouble with no way to stop in 3M. That's what you get for opening off-shape 1NT). And 1NT-2; 2-3 is a minor suit ask, GF but not necessarily SI. Also our 2 Stayman ask does not necessarily promise at least 4 cards in a major suit, and the auction 1NT-2; 2-2 shows an invitational hand without a 4cM (by contrast, 2NT shows 4 spades, NF, and higher bids are forcing and natural without promising a major). Nominally this is all just 'stayman and 4-way transfers', but which hands make which bids are highly dependent on the possible followups you have, and what hands partner would have opened 1NT on in the first place.

In my system we would bid:
1-2* (artificial, one of five hand types);
2* (relay, denies a non-minimum shapely hand)-2 (GF with spades);
3 (control, not a lousy minimum)-3 (promises spade ace or king, denies a heart control);
4 (last train, shows a heart control by inference, not enough extras for a Serious 3NT)-4NT (RKC 1430);
5 (1 or 4 keycards)-5 (off two aces);
P.
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