[ArcLight]

Assume 2/1 GF system -

In Danny Kleinmans excellent book "No Trump Zone" he discusses the forcing NT by an unpassed hand. He's fine with 1 ♠- 1NT - forcing.

But what do you do as opener with a minimum with 4 ♠ 5♥ and 2-2 in the minors (or maybe 3-1)?
You can't rebid 2 ♥, as that shows 6 ♥.
Bidding 2♠ is a reverse and you havent got the values.
Bidding a 2 card minor is not fun either, as you can end up in a 3-2 or 4-2 fit.

By bidding 1NT responder is probably denying 4 Spades. But you may want to end up in 2♠ rather than somewhere else.

His proposal is to swap the meaning of 1NT and 1♠ afetr a 1♥ opening bid.
Responder bids 1♠ over 1♥ to force for one round. If responder has spades he bids 1NT. If opener has a minimum 4=5=2=2 he "raises" partners 1NT (shopwing ♠) to 2♠, and responder can pass. If opener has a balanced hand, he can bid 1NT over pards 1♠ , probably right siding the 1 NT contract.

A weakness is if opener has a good balanced hand 1♥, with 18-19 HCP, which is between 1NT and 2NT. He will raise responsers 1NT to 2NT with the contract wrong sided.

Any thoughts on this method?
Weaknesses?
Worth the effort?
Too infrequent to worry about?

This came up in the authors discussion of Flannery.

[mr1303]

Ah yes, the Kaplin Inversion. Or at least a modification of it.

The trouble is with 1H P 1S P 2S showing 4 spades 5 hearts and a minimum is that responder might not like spades at all, and want to go back to 2H. Which of course can't be done.

What is typically done is that with 4-5-x-x hands, after 1H 1S opener bids 1NT to show 45 shape (as the 1S bidder can have 4 spades, just not 5), and with balanced hands (5332) opener bids his 3 card minor as if it had gone 1H P 1NT.

This is more of a problem than 1H 1NT(showing 5+ spades) 2NT having a wrong sided contract, since the 1H 1NT 2NT (in standard methods) is much more likely to wrong-side it.

[Gerben42]

Personally I think this is an excellent method BY AN UNPASSED HAND, not by a passed hand.
It has its drawbacks too.

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A weakness is if opener has a good balanced hand 1♥, with 18-19 HCP, which is between 1NT and 2NT. He will raise responsers 1NT to 2NT with the contract wrong sided.

Not much of a problem this, however this one is:

After 1♥ - 1♠, opponents have one extra bid to get Spades in the picture.

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Worth the effort?

Sure, just be sure to know if it applies
* for a passed hand (no)
* after opponents double (also no)

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Too infrequent to worry about?

Actually it is very frequent, a forcing NT response to 1♥ is too infrequent either

It is very related to F*** since it "solves" the same hands.

[bestguru]

hmm, seems that we could take this a step further and use 1♥ over 1♦ and 1♦ over 1♣ as the one round forcing responses. Of course you would have to make a few adjustments to openers rebids just like you do with 1♠ over 1♥.

Come to think of it you could go to the extreme by using 1♣ over pass as a one round force. hmm, wonder what a system like that would become

[Gerben42]

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Come to think of it you could go to the extreme by using 1♣ over pass as a one round force. hmm, wonder what a system like that would become 

That would be symmetric relay pass. Good system really!

1♣ - 1♦ F1R can be lot of things is true for many pairs even playing a semi-natural system. (Dutch Doubleton for example, 1♦ = negative, GF NT or natural)

[bestguru]

of course . I was just being silly for a moment. I really did think like that at one time though. I even "invented" the forcing pass. Then I did some research and found that all my innovations were old hat and it didn't matter anyways since I can't figure out which order to play the cards in.

[ArcLight]

>The trouble is with 1H P 1S P 2S showing 4 spades 5 hearts and a minimum is that responder might not like spades at all, and want to go back to 2H. Which of course can't be done.

I think opener bids 1NT rather than 2♠. I better check in the book, in case I have misspoken.

[MickyB]

Yes, he does, I think Mark misunderstood an ambiguity in your original post.

[Flame]

I think kaplan inversion is better then standard 1nt forcing, but i also think 1nt completly forcing is not a good idea.
One real problem about this is that you will forget it atleast few times till you get use to it.

[Kalvan14]

It is quite a good idea:

you can stop in 1N when it goes 1♥-1♠ (less than 4 ♠)-1N

if you have a ♠ fit, it goes 1♥-1N-2♠ (and it is likely to be played by the right side)

you right-side the NT contract whenever responder does not have ♠: 2 times out of 3, while the most common treatment does it 1/3 (when responder has ♠)

The only disadvantage I can see is that oppos can double 1♠ to show the suit: is it so dangerous?

[ArcLight]

The method I described seems ok to me, but I was told that it's not used by strong players. Its been around for a long time yet isn't used at the top. This implies it's not worth the effort.

I'm curious why. The only downside I see is allowing the opps to show interest in Spades at a low level, by doubling the 1 Spade (which is the forcing bid). Otehr than that, I don't think it hurts.

[mike777]

ArcLight, on Oct 27 2005, 12:10 PM, said:

The method I described seems ok to me, but I was told that it's not  used by strong players.  Its been around for a long time yet isn't used at the top.  This implies it's not worth the effort.

I'm curious why.  The only downside I see is allowing the opps to show interest in Spades at a low level, by doubling the 1 Spade (which is the forcing bid).  Otehr than that, I don't think it hurts.

I think you are getting ahead of a full analysis.

A better question is why is 1nt forcing better than 1nt semi-forcing?
Once you answer this question then I think you could move on to this next issue.
I prefer playing semi-forcing since now with 4522 and poor 11-12 hcp partner can pass 1nt. Note I do not mind playing in nt instead of potential 5-3 limit raise hand. With the opp bidding often if we are really weak, this becomes a rare issue.
With more I can rebid my 2 card club suit.

BTW Miles strongly prefers forcing nt so his 2/1 bids promise 5 card suits 100% so many issues to consider.

[keylime]

I am a fan of Kaplan inversion.

I am so NOT a fan of ACBL's insistence that this is Mid-Chart. Bah. Phooey. Yuck. Hiss. Boo.

[Chamaco]

ArcLight, on Oct 27 2005, 05:10 PM, said:

The method I described seems ok to me, but I was told that it's not used by strong players.

Buratti-Lanzarotti included a version of KI in their Nightmare system.