[fuburules3]

http://tinyurl.com/87fnd3b

I would prefer that 3♠ be forcing. At the very least, I don't think GIB should be allowed to pass with two little spades.

[georgi]

To be forcing it should be 17HCP also.

Also what information should 3♠ carries?
- I have 5 spades and I prefer 3♠ then 2NT
- I have 5 spades and I'm MAX and I want to play 3NT/4♠

It can't be invite as 2NT is invite as well, should be GF to what?

Very likely 3♠ shows 5 spades, so it's up to the points whether 3NT should be bidded or pass. If the declarer strength is random, just showing 5♠ then passing with 2nd and minimum shouldn't be that strange.

[fuburules3]

I think 3 ♠ should be accepting the invitation with 5♠ and letting partner decide whether he wants to play 4S or 3NT. Otherwise, it seems like an exceptionally bad bid (to potentially play in the 5-2 fit). I realize that I only have 15 points here, but typically it doesn't pay to play in 2NT vul at IMPS and I also assumed (correctly) that most of the field would probably be in 3NT.

 georgi, on 2011-December-12, 05:29, said:

To be forcing it should be 17HCP also.

Also what information should 3♠ carries?
- I have 5 spades and I prefer 3♠ then 2NT
- I have 5 spades and I'm MAX and I want to play 3NT/4♠

It can't be invite as 2NT is invite as well, should be GF to what?

Very likely 3♠ shows 5 spades, so it's up to the points whether 3NT should be bidded or pass. If the declarer strength is random, just showing 5♠ then passing with 2nd and minimum shouldn't be that strange.

[barmar]

This is an auction I've never seen in real bridge.

With a maximum and a 5-card major, you can make a jump response to Stayman. With a minimum, you give up on being able to show your 5-card suit.

[fuburules3]

If GIB's stayman promises invitational values (I don't know its system well enough to know), then I could see that a hand that is maximal with 5 spades would bid 3 spades in response to stayman. In that case, what sort of hand would ever bid 3S over 2NT? Normally playing "real bridge" if I'm accepting an invitation and I have extra length, I would bid suit along the way to give partner the option. I have not discussed this particular auction with any partners, but I think "bridge logic" dictates that 3S should be forcing (to reemphasize, I don't see why opener would ever want to play in the 5-2 spade fit over 2NT). This could just be my interpretation as this doesn't seem obvious to either of the people who have responded

 barmar, on 2011-December-12, 15:49, said:

This is an auction I've never seen in real bridge.

With a maximum and a 5-card major, you can make a jump response to Stayman. With a minimum, you give up on being able to show your 5-card suit.

[manudude03]

Of course 3S is forcing. Don't forget, North might only have a singleton, or even void! and if it has to bid 3NT on those hands, it follows that it has to bid something always.

[barmar]

Stayman normally promises invitational strength, but it can also be bid with a weak hand (even 0 HCP) and 4=4=5=0 shape, planning to pass any response. Even if opener jumps to 3 of a major you're OK because you have a 9-card fit.

[fuburules3]

Good point! Somehow I was operating in a world where responder always has at least 2 spades, which of course does not have to be the case.

 manudude03, on 2011-December-12, 20:12, said:

Of course 3S is forcing. Don't forget, North might only have a singleton, or even void! and if it has to bid 3NT on those hands, it follows that it has to bid something always.

[barmar]

This is an impossible auction. You can't have a GF hand with 5 spades, since you would have bid 3♠ earlier.

I've never seen this auction in real life.

Responder invited, and you had a minimum. Why are you bidding on?

[georgi]

That new suggestion of sequence seems unclear.

Why and when GIB should bid 3♠ ( because next time GIB will be your partner, but you responder over 1NT and the one who invites with 2NT). So GIB must be aware of the both sides logic, not just to bid something.

1NT - 2♣
2♥/2♠ - 2NT

In the hearts case we have another clue - partner doesn't have 4th♠ do invite with the other major in case opener had both.

So,
1NT - 2♣
2♥ - 2NT

could expect ♠[2-3]♥[2-3]♦[2-5]♣[2-5]. or hand like ♠[2-3]♥[2-3]♦[6]♣[2-3] or ♠[2-3]♥[2-3]♦[2-3]♣[6]

1NT - 2♣
2♠ - 2NT

could expect ♠[2-3]♥[2-4]♦[2-5]♣[2-5]. or hand like ♠[2-3]♥[2-4]♦[5]♣[2-3] or ♠[2-3]♥[2-4]♦[2-3]♣[5]

When do we pick 3♠. Just to show 5th ♠ or we have a worry suit?
But very likely if partner bids 2NT it has minimum values 8HCP with some distribution or 9 plain. So partner could already controls that suit.

Then comes the next scenario.
Partner has 4333 and 3rd in shown major. What has to bid here?

3♥/3♠ can't be semi forcing if partner has singleton or void in that suit. It should be clear bid. Pass or go up to game.
So if it's for pass partner can't move even if has singleton/void and staying with 3 cards.

Is there clear scheme what 3♠ should mean or we are just inventing particular bid for the particular hand?

Best solution would be global one, not specific which covers 0.001% games

[manudude03]

It seems simple to me. Opener should never be jumping to 3S. After all, aren't most of us bidding 2C with 3451 or possibly even 3460 or 3442 shapes (and completely broke)? As such, opener can never be sure of a 9 card fit. As for what gib is supposed to do with 3433, either just make it bid one way or the other always (I doubt people would be particularly bothered about which way to go) or make it simulate (setting opener to "5S; 2-3H; 2-3D; 2-3C; 16-17 HCP; 17 total points" or something), ideally in such a way that it can only choose 3NT or 4S.

[barmar]

 manudude03, on 2011-December-13, 08:52, said:

After all, aren't most of us bidding 2C with 3451 or possibly even 3460 or 3442 shapes (and completely broke)?

No. I bid Stayman with a weak hand last week, and I can't remember the last time I did it before that. I suspect the Stayman bidder has an invitational or better hand at least 98% of the time.

And remember, you only jump to 3♠ with a max. So the worst case is you play in an 8 card fit at the 3 level with a weak partner. But responder will have ruffing values.

[Yu18772]

 barmar, on 2011-December-12, 21:22, said:

This is an impossible auction. You can't have a GF hand with 5 spades, since you would have bid 3♠ earlier.
I've never seen this auction in real life.

Actually this is quite standard agreement imo, and I bid it plenty of times, with different partners and also saw it many times in real life. Jump responses to stayman are very impractical (and something that I havent seen in years) - it takes too much space, and often will not get you anywhere near a good contract, unless partner has a fit. After all partner will ask stayman on practically any hand with 4 card major and longer minor, and if you jump response in the other major what is 3NT now? what is 4minor? what is 4NT? - Jump response would require discussion and some special agreements to distinguish long minor, versus controls in partner's major, limits the exploration and has no merit by itself as this hand can easily be shown slower and safer (3M over any response). Consider a x, AQxx, AJxxxx, xx opposite 1NT. What do you bid over the 3♠ response by your partner? Is 4♦ showing real suit? then what about Kxxx, AQx, x, QT9xx?
To be absolutely clear - I dont argue that the OP is not a good hand to do this, but as agreement, bidding over the invitation is GF (unless shown suit) seems pretty standard to me.