[slyq]

interested in the subtelties of swaping 1s and 1nt in response to one heart
input appreciated.

[CamHenry]

More constraints appreciated! This is presumably a natural 1H, but is it limited? If 1H is 10-15, the implications are very different from if it's 11+.

How do you open 5=4 H/S hands that aren't worth a reverse? If 1S is possible canape, so 1H promises longer H, that's different again from 1H being possible canape, and again it's different if you play Flannery or similar so H is known to be your longest suit.

Let's assume 1H is 10-15 (so a strong minor system), and guarantees H as the longest suit. It could have a spade suit, but with equal length you open 1S. 1H denies a balanced hand, and promises 5H.

If you play 1H-1S to show a balanced hand, you gain all round:
- 1H-1S-2x shows something unsuitable for NT, usually 5-5 or more, or with very concentrated strength.
- 1H-1S-1NT shows a semi-balanced hand, possibly with values in a doubleton/singleton, and is a suggestion that NT may be a good strain. You can play 2C here as checkback, asking for a 6th heart or a 4+ card spade suit.
- 1H-1S-3x shows a maximum, very shapely, and is something that's almost but not quite good enough for your strong opening.

Responder can also play a split-range 1S: it could be 6-9 balanced, intending to pass 1NT or give simple preference, or it could be 15+ and wanting to force to game. Bidding again over 1H-1S-1NT would show the strong option; with an intermediate-strength balanced hand you'd make some other bid.

Now let's consider 1H-1NT, where 1NT shows spades. This is presumably forcing, unless you're going to play 1H-2S to show a forcing hand with spades. That means that you lose a fair few chances to play 1NT when it's right to do so. At matchpoints in particular, YUCK. This is the only real disadvantage - 1NT should be exactly as forcing as your natural 1H-1S would be, but opener is left without a good rebid on a 1=5=4-3 hand where the 4-card minor is weak. You may end up playing a 4-3 minor fit without many honours, or rebidding 2NT without any significant values, neither of which appeals.

Overall, I'd say the benefit outweighs the cost if your 1H opening is limited, but if your 1H opening is potentially strong (as in SAYC, for example) the ambiguity after 1H-1NT is going to hurt you too much.

One caveat: I've assumed both responses are permitted agreements in your jurisdiction. They are in the EBU (at all levels), but I don't know about other organisations.

EDIT: I've not played this sort of structure, so I'm going on analysis rather than experience. I've played 1H possible canape with any suit, after which 1S is an enquiry asking for 4+ spades. I can provide details of that if you like.

[Free]

Search "kaplan inversion"

[blackshoe]

Kaplan Inversion is not permitted at the GCC level in the ACBL.

[Free]

blackshoe, on Feb 22 2010, 02:46 PM, said:

Kaplan Inversion is not permitted at the GCC level in the ACBL.

Who cares? Forums is not 100% USA...

[Fluffy]

lol Frederick, now there are 3-4 americans who hate you , nevermind, you are not alone, they hate me as well

About kaplan inversion, or whatever you call it, the most common version shows 5+ spades, althou I play it as 4+ spades, not a biggie.

The main 2 advantages (IMO):

-You are much more likelly to wanna end up playing 1NT (1♥-1♠-1NT-pass) when you have a 1NT response (no spades) to 1♥ than when you have a 1♠ rebid. So you can achieve your goal now.

-You make the opener declarer in a spade part score, making the strong one declarer is right in the long run.

[blackshoe]

Free, on Feb 22 2010, 10:50 AM, said:

blackshoe, on Feb 22 2010, 02:46 PM, said:

Kaplan Inversion is not permitted at the GCC level in the ACBL. 

Who cares? Forums is not 100% USA...

I know that. I was replying to this:

camhenry said:

I've assumed both responses are permitted agreements in your jurisdiction. They are in the EBU (at all levels), but I don't know about other organisations.

The information I provided is pertinent, so you can stick your "who cares".

I don't hate anybody - I just can't abide people who don't read, or read and don't comprehend, what I write before they reply to it.

[Jlall]

blackshoe, on Feb 22 2010, 02:45 PM, said:

Free, on Feb 22 2010, 10:50 AM, said:

blackshoe, on Feb 22 2010, 02:46 PM, said:

Kaplan Inversion is not permitted at the GCC level in the ACBL. 

Who cares? Forums is not 100% USA...

I know that. I was replying to this:

camhenry said:

I've assumed both responses are permitted agreements in your jurisdiction. They are in the EBU (at all levels), but I don't know about other organisations.

The information I provided is pertinent, so you can stick your "who cares".

I don't hate anybody - I just can't abide people who don't read, or read and don't comprehend, what I write before they reply to it.

The anti american/anti acbl sentiment is very strong here, people like Free will often attack you if you mention anything about the ACBL, even in reply to a direct question/comment. It's pretty funny, don't worry about it.

As to the original question, imo the best advantages of KI are realized by playing the 1S response as 0-4 spades, and 1N as 5+ spades. Immediately knowing that partner has 5 spades is very useful (and imo the main benefit of flannery), and since partner has bid 1S you have room to sort out 4-4 spade fits still.

A common wait to play is that 1H-1S-1N shows 4 spades, and other bids are natural and as you would bid over a forcing NT. That is simple, and an improvement over natural, but imo you can do much better by playing transfers over 1S.

So 1H-1S-
1N=balanced or clubs
2C=diamonds
2D=6+hearts
2H=4S 5+H NF

The biggest advantage of this is that you can show your side suit and then bid again, eg 1H 1S 2C 2D 2H showing 6-4, or 1H 1S 2C 2D 2S showing something like a 3541 17 count, basically you get to have your cake (showing the 2nd suit) and eat it to (not risk getting passed in 2 of the minor opposite certain death hands).

Occasionally partner can also pass your transfer when you hit his long suit and he has a weak hand which is nice.

Meanwhile over 1H 1N showing 5+ spades you can bid naturally, bidding 2S with 3, the only problem shape now is exactly 2533 which must bid 2C.

[awm]

There do seem to be several different ways to play the follow-ups after 1♥-1♠. In my area (southern california) this method is popular among the better players but they all seem to play that opener's rebids are natural, so:

1NT = some balanced hand, or maybe a min 4522
2m = "natural", could be three if 45(13)
2♥ = natural
2♠ = natural with reverse values

This means you more or less have to respond 1♥-1NT with four spades, since you'd miss a lot of 4-4 fits otherwise. The main advantage of this approach seems to be letting you play 1NT more often opposite a balanced hand without four spades. Some of the players in my area like to play both Kaplan Inversion and Flannery on the same card!

The way I learned Kaplan Inversion, which I think is a lot better, is to play:

1NT = 4♠ with less than reverse values
Else = natural, 2m could be three if some balanced hand

This has the advantage of letting 1♥-1NT show five spades, such that you always find 5-3 spade fits and always avoid 4-3 spade fits. It seems like this approach gets the advantages of flannery without the disadvantages. It also lets responder sign off in a long minor suit at the two-level after 1♥-1♠-1NT.

As Justin mentions, playing transfer rebids could be the best approach, but it seems fairly unusual as best I can tell.

[PhantomSac]

awm, on Feb 22 2010, 05:26 PM, said:

It seems like this approach gets the advantages of flannery without the disadvantages.

Yeah this is how I've always described it heh.

Quote

As Justin mentions, playing transfer rebids could be the best approach, but it seems fairly unusual as best I can tell.

Yes I don't know many people who play it, I played it with Kev and I think Jdonn plays it (?) but don't know of anyone else, though I think I read it in print somewhere. Definitely unusual, but so is KI to begin with heh. If one finds transfers too difficult I still think it's hugely worthwhile to play a simpler version of KI.

[jdonn]

I would argue the transfer approach is clearly best.

In a strong club it's huge that responder can pass the rebid, especially if it's 1NT. Yes you can come up with some hand 5-5 with hearts and clubs or whatever where it would be wrong for responder to pass, but over time it has been huge for me to play 1NT on that auction.

In a more standard approach it's huge that opener can take 3 bids at a low level. Particularly when he is 6-4 in hearts and a minor and gets to show his shape and still play at 2♥ (or 3♥ if he is better).

Your approach seems better than the California one but still not quite right to me. You get neither of the above advantages, plus your diamond bid might be 3 instead of promising 4 as with transfers. It's true the transfer club bid is 3 more often but yours is still 3 sometimes, and it doesn't hurt as much if you can stop in 1NT anyway.

One other interesting idea, I think Gavin/Vince used to play 1NT showed diamonds and 2♣ was natural. I don't know enough about it to say much but I was told by a few people it worked really well the way they did it.

[Free]

Fluffy, on Feb 22 2010, 05:16 PM, said:

lol Frederick, now there are 3-4 americans who hate you , nevermind, you are not alone, they hate me as well

Some of them have hated me for years, so I might as well use that to my advantage
Just for the record: I don't like what I've heard and read about the way ACBL works.

As we are talking about continuations, I just want to mention that Gazzilli works as well. Other rebids are limited in strength, so there's not always a need to bid a 3rd time.

[slyq]

thanks all think i will play 1s as showing 3+ s and reverse gazilli seems to cope well with most hands ( 1h 1s 1nt shows 5332 min or 5h 4s min) luck all

[helene_t]

slyq, on Feb 25 2010, 12:18 PM, said:

thanks all think i will play 1s as showing 3+ s and reverse gazilli seems to cope well with most hands ( 1h 1s 1nt shows 5332 min or 5h 4s min) luck all

Should it read "3- spades" ?

Or are you playing reverse KI

[whereagles]

Most people I've seen playing this gadget have very simple follow-ups:

1♥ 1♠ (0-4 spades, forcing)
1NT = 4 spades, min (11 to bad 15 or so)
rest = normal natural bids

1♥ 1NT (5+ spades)
2x = normal natural bid. Can be 3 cards if 2m

[Rossoneri]

helene_t, on Feb 25 2010, 12:42 PM, said:

Or are you playing reverse KI

I'm confused, reversing an inversion?!

[Gerben42]

I'm playing this whenever I can, I really like it a lot. Still I must point out that now opps have a free Dbl of 1♠.

In an unlimited 1♥ context, I play Gazilli after 1♥ - 1♠, reserving 1NT for the Flann*** hands. I guess the lost step is worth the trouble since you can now actually play 1NT.

[straube]

I'm concerned that most of these structures prevent a 1N contract being reached. Not only may that be a good contract, but 1H-1S (natural), 1N leaves room for 2-way NMF.

How does one show GI with 5+ spades after 1H-1N?

Seems like you'll need 1H-2S to show something (6 spades GI?) and 1H-1S (denies 5 spades but could have 6 spades weak) so that 1H-1S, 2C-2S is weak with long spades.

[1eyedjack]

I used to play

1♥-1♠ = 0-4 Spades
1♥-1♠-1N = 5332 or 4x♦
1♥-1♠-2♣ = 6+♥
1♥-1♠-2♦ = 4x♠
1♥-1♠-2♥ = 4x♣ nf
you get the drift

The purpose was to get into 1N a bit more. We also liked the idea of being able to play in 2♥ rather than 3♥ when responder had a v weak hand and opener had some extras (if responder was good in context he would bid 2♦ over 2♣. That way if responder rebid 2♥ then opener knew to drop it unless he had a substantial hand. One downside is that if opener has 4x♠ and responder has fewer, then 1N may well be right. Another downside is the possibility of being forced to play in 3♣ when you might have preferred to play in 2♣. And the doubt about ♦ when opener rebids 1N. It's a numbers game.

On balance the numbers seemed to favour this treatment but for one additional problem: A particular problem with KI that I found was developing forcing sequences after 1♥-1♠ where responder is strong with 4 card ♠ suit. I found that I had to keep blasting 3N on the next round and could not investigate minor suit slams when opener rebid a minor in which I had 4 card support. But I was playing a fairly vanilla method and I expect this has been sorted out by others by now.

[PhantomSac]

1eyedjack, may I suggest not bidding 1S on strong hands with 4 spades? If you are balanced just bid 2C, and if you're unbalanced bid your longer minor. In fact I suggest this even not playing KI. Creating a GF quickly is great, starting with 1S then having to bid a new suit or an "impossible" 2S is really not great.