Invitational Jump Shifts

[pbleighton]

Not sure where this one belongs, but:

 

A partner and I are playing Precision, with 2/1 GF after 1M.

 

We are trying to decide the best use of jump shifts after 1M.

He doesn't like weak, I don't like Bergen. He suggests strong

or invitational with 6+. To me, if you play 2/1 GF, then strong

isn't that useful (comments?). Leaving invitational.

 

What do you think of it? It seems that it can patch a hole

after, say, 1S-1NT-3C, if you don't play WJS then 3C must

be weak.

 

What trump support should it show/deny?

 

Should 1H-2S be treated differently?

 

What you you play them as?

 

Peter

[Echognome]

After 1M, I think single jump shifts should either be fit jumps or mini-splinters. I think fit jumps are much more descriptive, but not as frequent. I like mini-splinters because they have other implications for our bidding. We play:

 

1M - single-jump shift = inv+ splinter. If GF, then responder has a singleton.

1M - double-jump shift = void splinter. (GF by definition)

1M - 2NT = inv+ raise. By implication shows a balanced hand.

 

I know many people splinter with singletons and voids, but I find that in order to bid the thin slams and grand slams, it's quite useful to know.

 

If playing fit jumps you need to decide whether it shows 3+ card trump support or 4+ card trump support. If the latter, more descriptive but less frequent. You also need to decide on the range of the hand. Invitational plus seems to be useful.

 

After 1m, weak jump shifts seem to be quite useful.

[MickyB]

When playing 2/1, I use a jump shift to the 3 level as either weak or invitational, and put the other range through 1N. Not sure which I prefer between weak and inv, probably weak by a short head.

 

Mike Lawrence recommends 1M:2m as GF unless suit rebid, and 1M:3m as strong. This handles the below GF hands well and the SJS hands fairly well, but loses out on the GFs that can't make a SJS.

 

I play all jumps to the 2 level as weak (5-8 or so), now bidding and rebidding your suit is constructive (9-11) and a jump rebid is GF.

[mr1303]

I've never been a fan of this 2/1 as GF unless suit rebid.

 

I want this sequence:

 

1S 2C

2 any 3C

 

to be 100% GF. If partner has no support at all for my suit, he can bid NT, and I haven't lost anything.

 

Suppose the sequence continues:

 

1S 2C

2D 3C

3NT

 

I can now bid 4C to show something approaching a real "Rock of Gibraltar" strong jump shift. However, these come up so infrequently, I see little point in wasting a jump shift to show this hand type.

 

With the more likely hand, xx Kx xx AQJTxxx I like to get my hand over to partner as quickly as possible; with an intermediate jump shift.

 

Thus

 

1S 1NT

2D 3C

 

can show a similar length suit, but with a less good suit, so partner is less likely to get excited

 

1S 2C

2NT 3C

 

can be a mild slam try

 

1S 2C

2NT 3C

3NT 4C

 

can be a full blooded slam try

 

and 1S 2C

2NT 4C can be RKCB

 

The suit should be equal to that of a vulnerable pre-empt, and should deny 3 card support for the major opening.

[flytoox]

If you play 2/1 as 100% GF, then you are forced to play 1M-3m as 9-11 concentrated invitational. This leaves 1M-1N;2x-3m to show weak 6-8.

 

However, I still think playing 2/1 as 95% GF, i.e. Lawrence's style, is better. Now you can play 1M-3m as fit bid.

 

As for what trump support it shows, I think it should be doubleton at best. Otherwise you can upgrade hand and respond 2m then bid 4M.

 

Regarding 1H-2S, I stil like strong jump shift.

[reisig]

Using jump shifts to 3 level as invitational with 6+ works very well...fills a gap in the 2/1 system. With fits ..can bid 2/1 then support.

[Antoine Fourrière]

I think a natural 3♣ response is useful whether you play it invitational or game forcing, but 3♦ should show some sort of fit, because with diamonds you can answer 2♦ anyway and play that a 3♣ rebid is an invitational-plus one-suiter and that a 3♦ rebid replaces what 3♣ would have shown, natural or fourth suit.

[Chamaco]

We are trying to decide the best use of jump shifts after 1M.

He doesn't like weak, I don't like Bergen.  He suggests strong

or invitational with 6+. To me, if you play 2/1 GF, then strong

isn't that useful (comments?).

 

The case of 1M opener and precision 1D opener are different.

 

When you open 1D, you do not have available 2/1 GF, so a jumpshift to 2M can be quite useful to set trumps.

 

When you have a slammish single suiter in a major and pard opens 1D in precision, you want to set the trump suit ASAP, frcing pard to accept that suit as trumps even if he holds a void (this will rarely happen if you start with a 1M response and bid slowly:pard will always refuse your long strong suit, since he is always short there)

If you start with 1M, you need a tool to set the trump suit as GF BELOW game (4th suit forcing is horrible for that).

 

So, if you do not use the strong jumpshift, you are almost forced to use 1D-1M-2C/D-3M as GF with selfsufficient suit (the strong JS-type hand) and not as invitational (as I said, using 4sf here is almost always a losing option).

 

This treatment is ok if you use the immediate jumpshift as invitational.

[MickyB]

So, if you do not use the strong jumpshift, you are almost forced to use 1D-1M-2C/D-3M as GF with selfsufficient suit (the strong JS-type hand) and not as invitational (as I said, using 4sf here is almost always a losing option).

 

This treatment is ok if you use the immediate jumpshift as invitational.

Or if you use it as weak!

[Chamaco]

So, if you do not use the strong jumpshift, you are almost forced to use 1D-1M-2C/D-3M as GF with selfsufficient suit (the strong JS-type hand) and not as invitational (as I said, using 4sf here is almost always a losing option).

 

This treatment is ok if you use the immediate jumpshift as invitational.

Or if you use it as weak!

Right, the meaning of 1S followed by 2S can be switched

[han]

I like to play 1M-1NT as non-forcing in a 100% GF 2/1 structure, and I think that this works best if 1NT denies 3-card support or an invitational 1-suiter. I think that this works well with invitational jump shifts and the 1M-2C structure that Ben often writes about (where 2C includes a 3-card limit raise).

 

Also, the 14-16 1NT (or 13-15) opening often used in precision fits very well with this, as you can pass 1M-1NT with all balanced hands.

 

I think that mini-splinters or fit-jumps are very valuable when they come up, but this is not very frequently. Contrary to invitational jump shifts, they don't really make the rest of the structure better.

 

BTW, is there anybody that has experience with a duo-jump shifts, i.e. 1M-3m as showing either a weak jump shift or a mini-splinter? I've seen this being used in a Dutch system called "snowface", the author claims that opener rarely has any problem identifying which kind of hand partner has.

[Chamaco]

I like to play 1M-1NT as non-forcing in a 100% GF 2/1 structure, and I think that this works best if 1NT denies 3-card support or an invitational 1-suiter. I think that this works well with invitational jump shifts and the 1M-2C structure that Ben often writes about (where 2C includes a 3-card limit raise).

 

If you play 2/1 absolute GF and 1NT is nonforcing, what do you bid with:

 

x-AKxxx-QJx-Jxxx

 

when pard opens 1 spades (10-15) ?

I suppose noone will suggest using 3 hearts as inv JS with this hand , and 2H is not an option (absolute GF).

 

Then one needs a more complcated structure than plain 2/1, a little like ETM full 2/1.

 

BTW, is there anybody that has experience with a duo-jump shifts, i.e. 1M-3m as showing either a weak jump shift or a mini-splinter?

 

Some time ago, I asked whether it could make sense a 2-way Jumpshift as showing EITHER a natural strong JS OR a fitshowing JS.

The only person that seemed interested was Ben (inquiry), but in any case I had no chance to give it a try so far...

[Echognome]

I guess it's a matter of style. Since we have limited openers, we play 1NT - any - 3m as the invitational hand. What do we do with the hand that wants to sign off? It's simple, we pass. If the opponents double we can run. At least I know it's not our hand in that case.

 

Thus, we have the single jumps free for whatever. I'm sure this method is not playable with an opening bid that can be 11-20 however. The other advantage of passing with some values (but a misfit) is that it makes it more dangerous for opponents to balance or compete.

[han]

If you play 2/1 absolute GF and 1NT is nonforcing, what do you bid with:

 

x-AKxxx-QJx-Jxxx

 

when pard opens 1 spades (10-15) ?

I suppose noone will suggest using 3 hearts as inv JS with this hand , and 2H is not an option (absolute GF).

I bid 1NT, not forcing. Perhaps I misunderstand your point, or perhaps my "non-forcing" suggests up to 10 HCP, but this is not what I meant.

[david_c]

I'd quite like to say, "DON'T play invitational jump shifts". The problem is that you're almost forced to play IJS if you're playing this style of 2/1, unless you want to leave some sorts of hands unbiddable. So what I really want to say is, "Don't play 2/1GF," except you won't want to hear that. Oh well.

 

Why are IJS horrible? Because

 

1. They don't completely solve the problem of how to bid invitational hands - there are plenty of hands where you have a long suit but you're not sure you really want to play in it.

 

2. Opener often doesn't know what to do, and doesn't have enough space to find out.

 

Having said that, when I play 2C as forcing to game, I play IJS. But they always seem to get us bad results.

[mr1303]

If you hate them so much, then why are they on our card.....

[david_c]

If you hate them so much, then why are they on our card.....

:rolleyes: Dunno. Possibly because the only decent solutions to this problem aren't allowed in EBU competitions until next year.

 

Actually, how about playing fit jumps over 1♥, weak jumps over 1♠?

[MickyB]

If you hate them so much, then why are they on our card.....

:( Dunno. Possibly because the only decent solutions to this problem aren't allowed in EBU competitions until next year.

Go on then David, elaborate ;)

[awm]

Invitational jump shifts seem to be very popular among top partnerships using a 2/1 game forcing system. It certainly fixes a big problem in auctions like:

 

1♠ - 1NT (forcing) - 2♦ - 3♣

 

If 3♣ promises invitational values, then you're forced to pass with a distribution like 1336, even though it will often be the case that 3♣ plays better than 2♦. However, if 3♣ carries the wide range of something like 6-11, partner will often be stuck. Another option is to play the jumps as something like 6-9... however most people I know who play "weak jump shifts" tend to use them on weaker hands than these.

 

My personal preference is to reverse the meaning of 2♦ followed by 3♦, and the direct 3♦ jump. So I'm playing "2/1 except suit rebid" instead of 2/1 GF. The reasoning is, take the following four hands:

 

(1) Ax KJx KQJxxx xx

 

(2) xx KQx KQJxxx xx

 

(3) x KJxx KQJxxx xx

 

(4) x AKxx KQJxxx xx

 

Playing 2/1 GF with intermediate jumps, you bid 2♦ followed by 3♦ on the first hand to force game. Notice that you're bidding 3♦ pretty much regardless of opener's second call -- you're not going to raise hearts in a 4-3 fit or spades on a 5-2 (assuming opener's 2♠ rebid doesn't guarantee six). On the second hand, you make an intermediate jump to 3♦. So far so good.

 

But hand three presents a problem. If you bid 3♦ (intermediate) it may be hard to find a heart fit. I wouldn't guarantee partner will bid 3♥ over this on four, especially with minimum values. Of course, if you bid 1NT (forcing) you're now really stuck if partner rebids 2♣ or 2♠, because you've already DENIED a single-suited invite with diamonds by not bidding 3♦ to begin with. Hand four is easy enough, you bid 2♦ and then you can rebid 3♦ or 3♥.

 

Playing 2/1 GF-except-rebid with single-suited GFing jumps, you bid 3♦ on the first hand. You haven't really lost much, because you were going to bid 3♦ on your second call anyway. On the second hand, you bid 2♦ followed by 3♦. Again no problems.

 

But hand three is now easy. You bid 2♦. If partner bids 2♥, your hand re-evaluates to a game force anyway and you can bid 4♥ (picture jump) to perfectly describe the hand. If partner bids something else, you rebid 3♦ (invitational).

 

Hand four is also no problem -- you start by bidding 2♦ and then if partner bids 2♠ or 2NT you can rebid 3♥ (natural, game forcing reverse with 4♥ and 5+♦).

[david_c]

... the only decent solutions to this problem aren't allowed in EBU competitions until next year. 

Go on then David, elaborate :D

When I've finished writing up my system I'll let you know. :)

 

But what I was referring to is that we're not allowed an artificial 2♣ bid which is not quite game-forcing, such as the one played by Ben.

[han]

In the US (I don't know where you are from David) an artificial 2C response is also not legal (in general convention chart), but you can get around this. 2C would be natural if it promises 3+ clubs. If you are 11-12 balanced without 3-card support (not sure if Ben includes this in 2C) then you always have 3 clubs, and when you have a 3-card limit raise then you usually have 3 clubs (almost always over 1H, as you have at most 3 spades). With less than 3 clubs, either overbid or bid a non-forcing 1NT. (of course, you can also "psych" a 2C response, but this seems unethical to me as you are knowingly "violating" a rule)

 

Funny consequence is that 1M-1NT-2m-3M shows at most 2 clubs!

[mr1303]

David is from sunny Manchester, like myself. We're limited by the EBU orange book, and as most of the competitions we play in are level III, this is even more strictly controlled.