[euclidz]

Watching play on a couple of occasions I have seen a response of 2NT over a 1 suit opening with responder holding 10-12hcp when they could have bid 2 of a suit at the 2 level. Playing just now (Acol 4cm's) partner opened 1♠ . . I had 3,3,3,4 with 3♠ and responded 2NT (i.e. re-bid the spades showing 5+ spades or go to 3NT). Partner passed explaining that she presumed I had just 10-12hcp. I presume this System/Convention has a name? And, I presume that someone is going to tell me it is Acol (the other Acol?)

[Vampyr]

The System/Convention is called "natural and invitational". I believe that it is part of standard Acol.

[ahydra]

Quote

The System/Convention is called "natural and invitational". I believe that it is part of standard Acol.

Yep - and since, like you say, a 2-over-1 response followed by 2NT communicates the hand perfectly well, Modern Acol and just about every other system in the world now use 2NT as some sort of raise of partner's major suit, which is much more useful.

Playing standard Acol, if you made the bid with more than 12 points expecting partner to bid again, unfortunately that is a mistake. As you said, it shows 10-12 HCP balanced with no fit; if partner can't envisage game opposite that, she will quite correctly pass.

ahydra

[Vampyr]

ahydra, on 2015-April-13, 15:07, said:

Yep - and since, like you say, a 2-over-1 response followed by 2NT communicates the hand perfectly well, Modern Acol and just about every other system in the world now use 2NT as some sort of raise of partner's suit, which is much more useful.

Actually most Acol players I know still play 2NT as nat and inv over a minor opening. I even play it myself with some partners.

[ahydra]

Vampyr, on 2015-April-13, 15:42, said:

Actually most Acol players I know still play 2NT as nat and inv over a minor opening. I even play it myself with some partners.

I do too . Edited my post.

ahydra

[helene_t]

If partner opens 1♦ and you hold a 3334 11-count it makes some sense to bid a natural 2NT since if you bid 2♣ partner may raise you to 3 on a (41)53 11-count. But it is a narrow target. OTOH, what else would it mean over a 1♦ opening?

Anyway, I would never use that bid undiscussed after a major suit opening. If it came up I would assume some kind of raise (who knows what the follows up are) unless the agreement was *basic* Acol in which case it is probably 10-12 balanced without a fit.

[euclidz]

Got the book out (Dormer/Klinger 2004) . . . . The 2NT response - You do not go out of your way to make this call on hands of borderline strength. To go down in 2NT when opener has an unsuitable minimum is bad. . . . Some partnerships (back in 2004!) no longer use 2NT as a limit response preferring the conventional Baron or Jacoby 2NT.

I can't see any advantage to raising to 2NT with 10-12hcp (unless it's pre-emptive?) and I can see all kinds of disadvantages.

[wank]

euclidz, on 2015-April-14, 07:11, said:

I can't see any advantage to raising to 2NT with 10-12hcp (unless it's pre-emptive?) and I can see all kinds of disadvantages.

the advantage is you get to game (it scores more) because partner knows you have a better hand.

[Jinksy]

helene_t, on 2015-April-14, 03:27, said:

If partner opens 1♦ and you hold a 3334 11-count it makes some sense to bid a natural 2NT since if you bid 2♣ partner may raise you to 3 on a (41)53 11-count. But it is a narrow target. OTOH, what else would it mean over a 1♦ opening?

All invites are trying to hit a narrow target.

[MrAce]

Jinksy, on 2015-April-16, 12:28, said:

All invites are trying to hit a narrow target.

Lanzarotti and Buratti tried to sell this idea long years ago and I actually tried it for a long time myself, you can see my posts in favour of this idea in BBF. Particularly at MP, it simply does not work. The target is actually wider than people anticipate. The difference in score is HUGE. Say you have extremely superior card play skills for the sake of argument, and you spared some bids for slam or whatever purposes when they are invitational bids for others. You need to make a 1 person guess between bidding games or simply just passing. This alone is extremely bad idea for a pair who has decent skills in play or defence. I say it is bad because it escapes me by a mile why would any pair with such skills would let themselves wide open to random results in bidding at MP. Why would anyone create such tuff guesses for themselves when the main goal of a good strategy in bidding is to avoid guesses which leads to either top or bottom in result?

While I say they are a MUST at MP, at IMP, especially K/O style imp, you probably have stronger ground. But even then it is debatable. Just checked some top pairs cc and/or notes, they all have invitation bids, some of them have it more than an average mainstream pair.

[helene_t]

Jinksy, on 2015-April-16, 12:28, said:

All invites are trying to hit a narrow target.

Right, sorry, I shouldn't have used that expression. What I meant is that you make a 2NT response in order to cater to opener having specifically (41)53 and 11-12 points.

[Vampyr]

helene_t, on 2015-April-14, 03:27, said:

OTOH, what else would it mean over a 1♦ opening?

Your weakest raise?

[Jinksy]

MrAce, on 2015-April-16, 16:03, said:

Lanzarotti and Buratti tried to sell this idea long years ago and I actually tried it for a long time myself, you can see my posts in favour of this idea in BBF. Particularly at MP, it simply does not work. The target is actually wider than people anticipate. The difference in score is HUGE. Say you have extremely superior card play skills for the sake of argument, and you spared some bids for slam or whatever purposes when they are invitational bids for others. You need to make a 1 person guess between bidding games or simply just passing. This alone is extremely bad idea for a pair who has decent skills in play or defence. I say it is bad because it escapes me by a mile why would any pair with such skills would let themselves wide open to random results in bidding at MP. Why would anyone create such tuff guesses for themselves when the main goal of a good strategy in bidding is to avoid guesses which leads to either top or bottom in result?

While I say they are a MUST at MP, at IMP, especially K/O style imp, you probably have stronger ground. But even then it is debatable. Just checked some top pairs cc and/or notes, they all have invitation bids, some of them have it more than an average mainstream pair.

Yeah, I just meant that if the logic works for them in general (which I'm not particularly doubting), it seems odd to single out a particular case - at least without providing reasons why the bid in that case would be better used for something else.