[weejonnie]

A natural bid is

"A bid of a suit which shows that suit (3+ cards) and does not show any other suit;" - 4C1 BB

So if 2♣ could be a 2 card suit then it must be alerted.

If it guarantees 3♣ then it is natural - now the words are "potentially unexpected meaning". In this case it is "potentially a forcing diamond raise". - And so alertable.

Since the auction

1♦ 2♣
2♦ 3♦ is forcing (presumably)then an alert for the 3♦ bid is probably correct as for many it may not be forcing.

"I think both opps just assumed this was normal bridge so there was no need to alert. "

Yet again players hiding behind the 'It's just bridge' to try and obfuscate opponents.

If ANYONE says that to me then they're getting a DP. Deliberate breach of law 20.F

[barmar]

Cyberyeti, on 2016-February-02, 12:50, said:

3 card suit is not so much of a problem, it's when they start doing it on 3352s that I think it should be alerted. Not sure if the same rules apply, but game tries that are 3+ cards are not alertable.

I think I've heard of players using 1♥ as the manufactured bid for hands like this. Even if partner raises, the Moysian may play OK (if he raises with 3, you can probably get out of the 3-3 fit).

[Vampyr]

weejonnie, on 2016-February-03, 10:34, said:

A natural bid is

"A bid of a suit which shows that suit (3+ cards) and does not show any other suit;" - 4C1 BB

So if 2♣ could be a 2 card suit then it must be alerted.

If it guarantees 3♣ then it is natural - now the words are "potentially unexpected meaning". In this case it is "potentially a forcing diamond raise". - And so alertable.

Since the auction

1♦ 2♣
2♦ 3♦ is forcing (presumably)then an alert for the 3♦ bid is probably correct as for many it may not be forcing.

"I think both opps just assumed this was normal bridge so there was no need to alert. "

Yet again players hiding behind the 'It's just bridge' to try and obfuscate opponents.

If ANYONE says that to me then they're getting a DP. Deliberate breach of law 20.F

So is any 2/1 which might have the values for game in partner's suit alertable? This would encompass a lot of 2/1s, in fact all 2/1s by pairs that don't play an immediate GF raise.

[barmar]

weejonnie, on 2016-February-03, 10:34, said:

If it guarantees 3♣ then it is natural - now the words are "potentially unexpected meaning". In this case it is "potentially a forcing diamond raise". - And so alertable.

"potentially" is an adverb modifying "unexpected", not an adjective modifying "meaning". So this should be interpreted as "a meaning that is potentially unexpected", not "a potential meaning that is unexpected".

So the question becomes how unexpected is it to invent a 2♣ bid when the system has no forcing diamond raise? Is it really much different from 1♠-2♣ holding GF 3433 (many players use 3NT to show this, to avoid the need for the invented suit, although this is typically a narrow HCP range and you have to come up with something else for stronger hands).

[Cyberyeti]

barmar, on 2016-February-03, 11:12, said:

"potentially" is an adverb modifying "unexpected", not an adjective modifying "meaning". So this should be interpreted as "a meaning that is potentially unexpected", not "a potential meaning that is unexpected".

So the question becomes how unexpected is it to invent a 2♣ bid when the system has no forcing diamond raise? Is it really much different from 1♠-2♣ holding GF 3433 (many players use 3NT to show this, to avoid the need for the invented suit, although this is typically a narrow HCP range and you have to come up with something else for stronger hands).

I don't think you should need to know whether they're playing a forcing diamond raise or not. As a lot of people do play one, this meaning is potentially unexpected. Rather less people play a GF 3 card raise of 1M (particularly in the UK where 4M is still common), so I think the 3 card 2♣ would fall under GBK.

[weejonnie]

Cyberyeti, on 2016-February-03, 11:53, said:

I don't think you should need to know whether they're playing a forcing diamond raise or not. As a lot of people do play one, this meaning is potentially unexpected. Rather less people play a GF 3 card raise of 1M (particularly in the UK where 4M is still common), so I think the 3 card 2♣ would fall under GBK.

General bridge knowledge is something that would be an agreement without discussing with a new partner. I fail to see how a response on 3 card suit at the 2 level at the first opportunity as being potentially a forcing diamond raise would fall into this category.

[Cyberyeti]

weejonnie, on 2016-February-03, 12:13, said:

General bridge knowledge is something that would be an agreement without discussing with a new partner. I fail to see how a response on 3 card suit at the 2 level at the first opportunity as being potentially a forcing diamond raise would fall into this category.

I think it would be assumed in the partnership as soon as the discussion got as far as "inverted minors - no", but should not need to be by opps. I was talking about the 3433 2♣ response to 1♠ as GBK.

[Vampyr]

weejonnie, on 2016-February-03, 12:13, said:

General bridge knowledge is something that would be an agreement without discussing with a new partner. I fail to see how a response on 3 card suit at the 2 level at the first opportunity as being potentially a forcing diamond raise would fall into this category.

Yeah, this is why Cyberyeti said it was "potentially unexpected".

I don't think that GBK covers any bidding agreements at all, but any case I lean strongly toward non-alertable on this one. This is because it may not be an agreement, but instead made up on the spot.

[barmar]

Vampyr, on 2016-February-03, 12:33, said:

Yeah, this is why Cyberyeti said it was "potentially unexpected".

I don't think that GBK covers any bidding agreements at all, but any case I lean strongly toward non-alertable on this one. This is because it may not be an agreement, but instead made up on the spot.

It's one of those things that just about everyone "makes up" the same way. So it seems like an agreement or convention, but it's really more a consequence of common bridge logic. It's like reversing or jump-shifting into a 3-card suit as a solution to the MSC death hand -- every experienced player eventually runs into this situation, and usually comes up with the same solution.

[helene_t]

barmar, on 2016-February-03, 14:43, said:

It's one of those things that just about everyone "makes up" the same way. So it seems like an agreement or convention, but it's really more a consequence of common bridge logic. It's like reversing or jump-shifting into a 3-card suit as a solution to the MSC death hand -- every experienced player eventually runs into this situation, and usually comes up with the same solution.

I don't really buy this. It may be true that most systems have holes that require you do deviate, and it may be GBK that in such cases you are more likely to everstate minor suit length than major suit length. But in which situations this applies is system dependent.

The OP case was a situation in which the pair did not have a forcing minor suit raise. It is not GBK that a respond in the other minor can be fake unless you play in an environment where most people don't have a forcing minor suit raise, and even then it may well be that most pairs will use a jump shift (or Gerber or whatever) instead of a simple shift.

The "Death hand" is only a death hand if you play a system in which it is a death hand. Maybe in some areas most people play such a system so it is GBK, but then you might still have to alert it if you go to a country in which most people don't play such systems.

Case in point: Playing forcing 1NT (or just a strong notrump system in which 5M332 is not normally opened 1NT),
1M-1NT
2♣*
can be a 3-card suit. I believe that is not alertable in ACBL. It is not alertable in NBB. But it is in EBU. This is not about different attitudes to alerting, it is about differences in locally popular systems.

[Vampyr]

helene_t, on 2016-February-04, 04:06, said:

Case in point: Playing forcing 1NT (or just a strong notrump system in which 5M332 is not normally opened 1NT),
1M-1NT
2♣*
can be a 3-card suit. I believe that is not alertable in ACBL. It is not alertable in NBB. But it is in EBU.

Are you sure?

[Cyberyeti]

Vampyr, on 2016-February-04, 09:22, said:

Are you sure?

Used to be alertable in precision also when I used to play it, definitely potentially unexpected.

[barmar]

I think it also used to be alertable in ACBL. But I think the game-forcing 2/1 response was also alertable at that time. Our alerting regulations evolve as the popularity of different bidding systems change. With the majority of players either playing 2/1 or encountering it so much that they can't help but be familiar with it, we've stopped alerting bids whose meanings come from common inferences. The same happened with Walsh-style responses to 1♣ openings.

[steve2005]

How often will these manufactured bids come up? 1/100, 1/1000
If you start alerting these rare possible bids pretty soon your alerting every bid because there is some chance partner could be bidding out of system. Once you alert everything you might as well alert nothing as it serves no purpose.

[Cyberyeti]

steve2005, on 2016-February-04, 16:12, said:

How often will these manufactured bids come up? 1/100, 1/1000
If you start alerting these rare possible bids pretty soon your alerting every bid because there is some chance partner could be bidding out of system. Once you alert everything you might as well alert nothing as it serves no purpose.

It's not partner making a bid out of system, it's alerting your opponents that this is a bid which might cover a hole in your system where there is a not unusual situation (GF diamond raise without another suit) and no system bid.

[Zelandakh]

barmar, on 2016-February-03, 11:12, said:

So the question becomes how unexpected is it to invent a 2♣ bid when the system has no forcing diamond raise?

This is a genuinely silly argument Barry. How unexpected is it to be playing a natural 2♣ opening when the system uses a strong or mixed 1♣? I would imagine you would still expect to be alerted of the fact. As soon as you make alerts dependent on the opps understanding how the pair's system works, you are really making the system worthless. GBK should never be dependent on understanding hidden parts of a system you have never played!

[barmar]

Zelandakh, on 2016-February-05, 09:10, said:

This is a genuinely silly argument Barry. How unexpected is it to be playing a natural 2♣ opening when the system uses a strong or mixed 1♣? I would imagine you would still expect to be alerted of the fact. As soon as you make alerts dependent on the opps understanding how the pair's system works, you are really making the system worthless. GBK should never be dependent on understanding hidden parts of a system you have never played!

That's not a fair argument, because the alert regulations specifically say that strong 2♣ is the non-alertable meaning, and anything else is alertable. We only fall back on the "potentially unexpected" (or ACBL's "highly unusual and unexpected") criterion when dealing with bids that the regulations don't directly address.

It's also the general spirit that guides the people who create the alerting regulations in the first place. If we required pre-alerting of a strong club system, it might not be unreasonable for that to obviate alerting a natural 2♣.

[Cyberyeti]

Of course in the EBU you announce the intermediate 2♣ and alert the big artificial version (although a lot of people announce it as well).