[Trinidad]

 FrancesHinden, on 2012-December-31, 16:20, said:

Is it AI to the EW players that neither N or S ever asked about the meaning of the (alerted) 2D bid?
Should that affect the ruling about opening leader's LAs?

That would be AI to EW.

This also changes my view on the case. I had assumed that NS knew that 2♦ showed the pointed suits.

Now it starts to remind me of a case that happened when I was playing against two LOLs: LHO opened 1NT and my partner overcalled 2♥, alerted because it was DONT. Nothing was asked and RHO bid 2♠. I passed, LHO bid something, partner passed and now suddenly RHO asks me what 2♥ meant. I told her it showed both majors. RHO rebids her spades with 3♠, promptly alerted by LHO: It asks for a spade stopper. LHO bids 3NT, partner leads and indeed, dummy hits with five spades to the 9.

Rik

[nige1]

TFLB L40B6a said:

When explaining the significance of partner's call or play in reply to opponent's enquiry (see Law 20) a player shall disclose all special information conveyed to him through partnership agreement or partnership experience but he need not disclose inferences drawn from his knowledge and experience of matters generally known to bridge players.

The law-makers may have intended to exempt players from explaining facts obvious to almost all bridge players. e.g. "spades outrank hearts". Unfortunately some Bridge-players seem to interpret this more liberally and use it as an excuse for nondisclosure. I often find that I don't know things that other players say are generally known. But I don't see the relevance of GBK here. At the end of the auction, if I ask and and both opponents confirm that their calls are natural, I'm naive enough to believe them.

 FrancesHinden, on 2012-December-31, 16:20, said:

Is it AI to the EW players that neither N or S ever asked about the meaning of the (alerted) 2D bid?
Should that affect the ruling about opening leader's LAs?

This is too deep tor me

• What is the answer to Frances' first question?
• But even if it is AI, assuming that the EW system-card explains the 2♦ bid, then it might be dangerous to read much into the lack of a question.

[barmar]

 ArtK78, on 2012-December-31, 16:36, said:

My RHO put the lead face down and then my LHO asked my partner about the meaning of the 3♠ bid. Both I and my partner broke out laughing. Our explanation was essentially that this was the first board we have played together in about 10 years and our pregame discussion did not include how to invite a game after we pass a hand out in partscore.

Nevertheless, he understood, through general bridge knowledge, that I had something of value in spades (I had QTxx), and we made 3NT on a heart lead into his AQ.

Would anyone argue that we need to come up with a better explanation for my 3♠ bid?

It's pretty common that when the opponents have shown one suit, a cue bid asks if partner can stop the suit, while when they've shown two suits the cue bid tells that you can stop that suit, and asks if partner can stop the other one (this assumes that there's room in the auction for you to bid both suits). I would consider this to be GBK among reasonably advanced players, but not all players in general. If I felt my partner were of the same experience level as myself, I would consider it an implicit agreement and disclose it to the opponents if asked.

In fact, even in less complicated auctions I've occasionally had opponents ask about a cue bid "was he asking or showing?"

[Trinidad]

 nige1, on 2013-January-01, 03:12, said:

The law-makers may have intended to exempt players from explaining facts obvious to almost all bridge players. e.g. "spades outrank hearts". Unfortunately some Bridge-players seem to interpret this more liberally and use it as an excuse for nondisclosure.

I think the law makers intended the term "general bridge knowledge" as an opposite to "pair specific bridge knowledge" (the agreements and understandings that you have as a pair, whether explicit or implicit through partnership experience).

This means that "general bridge knowledge" includes all knowledge, experience and skills that an individual player has which is not related to his partnership with this particular partner.

If I am paired to a mr. Hong Wang from Beijing, without time to discuss anything, we both will only have our own GBK to fall back on. On the first board, the opponents are not entitled to any information about our bidding. I think that Mr. Wang and I would get by reasonably well, which means that GBK plays a significant role in bridge.

 nige1, on 2013-January-01, 03:12, said:

But I don't see the relevance of GBK here. At the end of the auction, if I ask and and both opponents confirm that their calls are natural, I'm naive enough to believe them.

Sure. But there is a subtle difference between saying that the individual calls are natural (promising length/strength) and saying that the auction was natural.

If I play an entirely natural system am I not allowed to open 1♠, rebid 2♥, followed by 3♦ and finally bid 4♣ unless I have 16 cards in my hand? And if my partner bids like that am I not allowed to think that he probably doesn't have four clubs? And now the more delicate question: Do I need to tell my opponents that my partner doesn't hold 3 clubs, despite the fact that the auction was natural?

Rik

[aguahombre]

Rik has, IMO, nailed the difference between GBK in general and GBK which must be disclosed when a question is asked. At risk of restating the obvious, just in case it isn't really obvious to everyone, here is what we do and what we believe is right to do:

When asked, we disclose anything which we consider GBK if it is also part of our partnership experience...either discussed, or having occurred previously at the table; we believe it is our obligation to do so. We do not believe we should disclose what we consider to be GBK otherwise, but since we have been playing together since Christ was a corporal, nearly every situation is part of our partnership experience. "I take her call to mean..." should never be used.

The bidding by South in the OP would not be part of our partnership experience

[pran]

 Trinidad, on 2013-January-01, 09:14, said:

I think the law makers intended the term "general bridge knowledge" as an opposite to "pair specific bridge knowledge" (the agreements and understandings that you have as a pair, whether explicit or implicit through partnership experience).

This means that "general bridge knowledge" includes all knowledge, experience and skills that an individual player has which is not related to his partnership with this particular partner.

[...]

I have always understood the clause about "general bridge knowledge" to allow when explaining an auction not wasting time by including information that opponentes should be expected to know already.

It doesn't make sense to me if this clause is meant to allow a partnership avoiding disclosure of information "generally known to themselves" while not also obviously known to their opponents.

[aguahombre]

 pran, on 2013-January-01, 10:21, said:

I have always understood the clause about "general bridge knowledge" to allow when explaining an auction not wasting time by including information that opponentes should be expected to know already.

It doesn't make sense to me if this clause is meant to allow a partnership avoiding disclosure of information "generally known to themselves" while not also obviously known to their opponents.

I do not like the idea of expecting the opponents to know something, or of judging what is or should be "obviously" known by them. The criterion should be whether WE are using GBK to try something new on partner (not disclosable), or whether we are using a call which we understand from our partnership's experience (disclosable).

Wasting time should not be a concern, if a question is asked. I would probably waste more time trying to decide whether the opponents should already know something than just explaining the call.

[pran]

 aguahombre, on 2013-January-01, 10:37, said:

I do not like the idea of expecting the opponents to know something, or of judging what is or should be "obviously" known by them. The criterion should be whether WE are using GBK to try something new on partner (not disclosable), or whether we are using a call which we understand from our partnership's experience (disclosable).
[...]

So you want to legally conceal your implicit partnership understandings from your opponents by claiming that this is General Bridge Knowledge to you and your partner, not worrying about whether it may be known or unknown to your opponents?

I don't care to express what I think.

[Trinidad]

 pran, on 2013-January-01, 13:49, said:

So you want to legally conceal your implicit partnership understandings from your opponents by claiming that this is General Bridge Knowledge to you and your partner, not worrying about whether it may be known or unknown to your opponents?

I don't care to express what I think.

I think you misunderstand what aguahombre is writing. Perhaps because you mistakenly think that when he writes 'we' it refers to him and his partner. It doesn't. 'We' refers to aguahombre and 'us': the people that "look over aguahombre's shoulder" at the situation that he describes.

He was very clear that all implicit partnership understandings should be disclosed, because they relate to the partnership. What in his (and my) opinion does not need to be disclosed is individual bridge knowledge, i.e. all things that have nothing to do with the partnership.

Rik

[nige1]

 Trinidad, on 2013-January-01, 09:14, said:

I think the law makers intended the term "general bridge knowledge" as an opposite to "pair specific bridge knowledge" (the agreements and understandings that you have as a pair, whether explicit or implicit through partnership experience). This means that "general bridge knowledge" includes all knowledge, experience and skills that an individual player has which is not related to his partnership with this particular partner.

 aguahombre, on 2013-January-01, 09:55, said:

Rik has, IMO, nailed the difference between GBK in general and GBK which must be disclosed when a question is asked. At risk of restating the obvious, just in case it isn't really obvious to everyone, here is what we do and what we believe is right to do: When asked, we disclose anything which we consider GBK if it is also part of our partnership experience...either discussed, or having occurred previously at the table; we believe it is our obligation to do so.

 pran, on 2013-January-01, 10:21, said:

I have always understood the clause about "general bridge knowledge" to allow when explaining an auction not wasting time by including information that opponents should be expected to know already. It doesn't make sense to me if this clause is meant to allow a partnership avoiding disclosure of information "generally known to themselves" while not also obviously known to their opponents.

I prefer Sven's interpretation i.e. you should disclose your relevant "general" bridge knowledge unless you're confident that opponents already share it. I fear, however, that most Bridge-players agree with Trinidad and Aquahombre.

[blackshoe]

"Obvious" is a very slippery word — what's 'obvious' to me might not be 'obvious' to Sven and vice versa, and you can substitute any names you like in there. It seems to me where people are going with this is that unless you know your opponents very well, you should assume nothing about what they know. I suppose this fits well with "the principle of full disclosure", since it will cause you to mention things you might otherwise consider "matters generally known to bridge players". it's likely to annoy some players though.

[Trinidad]

 nige1, on 2013-January-01, 16:28, said:

I prefer Sven's interpretation i.e. you should disclose your relevant general bridge knowledge unless you're confident that opponents already share it. I fear, however, that most Bridge-players agree with Trinidad and Aquahombre.

You can prefer what you prefer, but meanwhile the law is pretty clear: you do not need to disclose general bridge knowledge, only knowledge about partnership agreements, in the broadest sense of the word (explicit, implicit, ranges, style, the meaning of alternative calls, etc.).

It doesn't make sense to me either to disclose to the opponents what I can infer through my general bridge knowledge what my partner might not be able to infer (because he lacks that general bridge knowledge).

Rik

[pran]

To me "General bridge knowledge" within a partnership constitutes part of their partnership understanding. It doesn't matter whether this knowledge is the result of common or individual experience, discussion, reading or whatever. And for the question on disclosure it is completely irrelevant whether partnership understanding is explicit or implicit.

The purpose of the laws on disclosure is to ensure that opponents have the same foundation for understanding the calls as the players using the calls. To me it is obviouos that what you do not need to disclose is knowledge that opponents must be expected to already possess, it does not include knowledge that in any way is "general" for the players using it but not neccessarily to opponents.

Failing to disclose such knowledge comes very close to using concealed partnership understanding, a matter about which the laws are very severe.

[barmar]

If my partnership had an auction that started with a Jacoby 2NT response to a major opening, and the opponents asked for an explanation of the auction, we would explain 2NT and all the followons. The meaning of the initial opening bid would fall under GBK, and few would think of explaining it or complain about the lack of explanation (practically everyone around here plays 5-card majors).

On the other hand, if a Precision pair had a similar auction, I would expect them to mention that the opening was limited when explaining, but they still needn't mention that it shows a 5+ suit.

If someone else feels like including that detail in their explanations, that's fine. I just don't think it's required.

[pran]

 barmar, on 2013-January-01, 18:41, said:

If my partnership had an auction that started with a Jacoby 2NT response to a major opening, and the opponents asked for an explanation of the auction, we would explain 2NT and all the followons. The meaning of the initial opening bid would fall under GBK, and few would think of explaining it or complain about the lack of explanation (practically everyone around here plays 5-card majors).

On the other hand, if a Precision pair had a similar auction, I would expect them to mention that the opening was limited when explaining, but they still needn't mention that it shows a 5+ suit.

If someone else feels like including that detail in their explanations, that's fine. I just don't think it's required.

It depends on the competence of opponents. If unsure it should be mentioned.

Ruling on possible misinformation will often be an after the fact assessment on whether the omitted information turned out to be important.

[Trinidad]

 barmar, on 2013-January-01, 18:41, said:

If my partnership had an auction that started with a Jacoby 2NT response to a major opening, and the opponents asked for an explanation of the auction, we would explain 2NT and all the followons. The meaning of the initial opening bid would fall under GBK, and few would think of explaining it or complain about the lack of explanation (practically everyone around here plays 5-card majors).

On the other hand, if a Precision pair had a similar auction, I would expect them to mention that the opening was limited when explaining, but they still needn't mention that it shows a 5+ suit.

If someone else feels like including that detail in their explanations, that's fine. I just don't think it's required.

That is a wrong example. Playing 5 card majors is a partnership agreement. It needs to be disclosed.

There is a simple test of what is general bridge knowledge and what are partnership agreements. Partnership agreements can only be improved when both partners play, discuss or practice together. General bridge knowledge can be improved by playing with anybody or by reading a book (except when it was written by your partner ).

An example of general bridge knowledge is how people evaluate the structure or honor location in the hand. Certainly for occasional pairs, but also for most others, this has nothing to do with specific partnership agreements. It is the hand evaluation skill or experience of the individual player and it may well be (usually is) different between the two players. The more you play in general (regardless of whom you play with), the better you get at it. Your partnership agreements can only be improved by playing (or discussing) with your partner.

Rik

[Trinidad]

 pran, on 2013-January-01, 18:39, said:

To me "General bridge knowledge" within a partnership constitutes part of their partnership understanding. It doesn't matter whether this knowledge is the result of common or individual experience, discussion, reading or whatever.

Sven, how do you disclose to the opponents the general bridge knowledge that is the result of the individual experience of your partner?

Rik

[Vampyr]

 FrancesHinden, on 2012-December-31, 16:20, said:

Is it AI to the EW players that neither N or S ever asked about the meaning of the (alerted) 2D bid?

Please, Frances, say that this is tongue-in-cheek and that you never in a million years would think this is AI?

[blackshoe]

 barmar, on 2013-January-01, 18:41, said:

If my partnership had an auction that started with a Jacoby 2NT response to a major opening, and the opponents asked for an explanation of the auction, we would explain 2NT and all the followons. The meaning of the initial opening bid would fall under GBK, and few would think of explaining it or complain about the lack of explanation (practically everyone around here plays 5-card majors).

On the other hand, if a Precision pair had a similar auction, I would expect them to mention that the opening was limited when explaining, but they still needn't mention that it shows a 5+ suit.

If someone else feels like including that detail in their explanations, that's fine. I just don't think it's required.

I don't think it's GBK that a Precision 1M opening is 5+ cards, because the structure of Precision is not known to all players. So I think 5+ cards is disclosable.

In fact, when a question is asked, it seems to me that the principle of full disclosure requires me to mention that my 1M opening is on 5+ cards, whether I'm playing Precision, SA, 2/1, Romex, Romex Forcing Club, KS, RS, or any other 5 card major system, because the length of the suit is a matter of partnership agreement.

You already know that in many (perhaps most modern) systems a 1M opening is on 5+ cards, so you're happy not to have that explained. Not every other player in the world will be happy with that.

[pran]

 Trinidad, on 2013-January-01, 20:46, said:

Sven, how do you disclose to the opponents the general bridge knowledge that is the result of the individual experience of your partner?

Rik

When I explain my partner's auction I disclose what I know (that I think is pertinent) without bothering about how I know it.

You should focus on what you are required to disclose, not on what you may leave out.