[rgheath]

I am working my way through Mike Lawrence'd instructional CD on 2/1. I see that he recommends the use of invitational JS at the 3 level . That is 1X- 3Y where Y is a lower ranking suit. Applies when X is majors or diamonds. You have to give up Bergen raises and Mike usually gives the pros/cons of various treatments but does not say much on this issue other than you have to give up Bergen. Can anyone point me to an article, book that discusses this point. Also how common is the usage of invitational JS at the expert level?

Ron

[MickyB]

IMO you need to be able to split the hands short of GF values into two ranges - invitational and weak. If you play 2/1 as totally GF, then your jump-shifts need to cover one of these ranges. I'm not sure whether I prefer WJS or IJS.

In his book on 2/1, Lawrence suggests that sequences like 1S:2C, 2S:3C should be invitational. IIRC 1S:3C is then a strong-jump shift. Personally, I'd be quite happy to lose Bergen raises.

[inquiry]

MickyB, on Jan 25 2005, 02:59 PM, said:

Personally, I'd be quite happy to lose Bergen raises.

I love 1S-3S to be weak preemptive raise.... This is the "reason" many choose to play Bergen. The enlightened (aka, me... ) use a limit raise or better "jacoby 2NT" so all the bergen hands are rolled into that bid... this leave 3♣ and 3♦ to be whatever you want... weak jump shift, strong jump shift, invitational with the suit, fit jump. It is up to you. I use to use them for fit jumps, but I have switched to invitational with bid suit which seems more useful.

Ben

[pclayton]

I play these with the partners that insist on "2/1 = 100% GF". Otherwise the 1N response gets overloaded with 5-12 point single suiters.

Of course, I prefer to play Lawrence style where a 2/1 isn't a 100% GF/

[whereagles]

inquiry, on Jan 25 2005, 08:09 PM, said:

MickyB, on Jan 25 2005, 02:59 PM, said:

Personally, I'd be quite happy to lose Bergen raises.

I love 1S-3S to be weak preemptive raise.... This is the "reason" many choose to play Bergen. The enlightened (aka, me... ) use a limit raise or better "jacoby 2NT" so all the bergen hands are rolled into that bid... this leave 3♣ and 3♦ to be whatever you want... weak jump shift, strong jump shift, invitational with the suit, fit jump. It is up to you. I use to use them for fit jumps, but I have switched to invitational with bid suit which seems more useful.

Ben

Funny you mention this. I cooked up a scheme of major suit raises which very much looks like yours. The only difference is I play 1M 3x as an inv+ splinter. Since the splinter is given at a very low level, you have loads of bidding space to find out about extras/voids, etc.

[luke warm]

why (and when) did the under & over jump shifts lose favor? you know, under j/s showing a limit splinter and over j/s a stronger one? it makes it simple to show the bergen constructive and limit bids that are more balanced (for example, 1H/3D would be an under j/s so 1H/3C would show 7-11.. 3D by opener, if he'd go to game vs. a limit raise, asks which type raise responder has)

[mr1303]

I play them because I think you lose a lot of space if you play that:

1S 2C
2 bananas 3C

is not forcing. If I have to jump to the 4 level to show a game force with 6+ good clubs I want to play another system.

Generally I find that the difference between the 6-9 Bergen raise and the 6-9 3 card support (single raise) is not so necessary, so as long as you can make pre-emptive and limit raises without overloading J2NT. 1 pair I know uses their Jacoby 2NT as limit +, but all of their continuations are designed for deciding when to bid game and when to stop in 3. Pointless

[whereagles]

luke warm, on Jan 26 2005, 02:10 AM, said:

why (and when) did the under & over jump shifts lose favor? you know, under j/s showing a limit splinter and over j/s a stronger one? it makes it simple to show the bergen constructive and limit bids that are more balanced (for example, 1H/3D would be an under j/s so 1H/3C would show 7-11.. 3D by opener, if he'd go to game vs. a limit raise, asks which type raise responder has)

Well, you can use, say

1H 2S = inv splinter (any suit)
1H 3C = strong splinter (any suit)
1H 3D = very strong (or void) splinter (any suit)

but I prefer to use

1H 2S/3C/3D = inv+ splinter

because it gives the shape right away, and can occasionally save a tiny bit of bidding space.

[han]

I feel that these invitational jump shifts are a must, as I really want to play a semi-forcing 1NT response. Hands with a good long suit (especially hearts over spades)often play really well opposite a fitting hand, and I would hate to bid 1NT with them.

I also play 2NT as limit raise or better and 3M as weak as others do. I have played this for several years now and I'm quite confortable with it. I don't think that this overloads Jacoby 2NT, and there are many good Jacoby structures on the market.

Since recently I play that we bid 1M-2C with a 3-card limit raise to further unload the 1NT response. This requires some serious discussion, but I think that this is a big improvement for the whole structure.

[inquiry]

Hannie, on Jan 26 2005, 05:05 PM, said:

Since recently I play that we bid 1M-2C with a 3-card limit raise to further unload the 1NT response. This requires some serious discussion, but I think that this is a big improvement for the whole structure.

I like this too... drury after all seats is neat

[flytoox]

inquiry, on Jan 26 2005, 09:28 PM, said:

Hannie, on Jan 26 2005, 05:05 PM, said:

Since recently I play that we bid 1M-2C with a 3-card limit raise to further unload the 1NT response. This requires some serious discussion, but I think that this is a big improvement for the whole structure.

I like this too... drury after all seats is neat

Ben, I remember a BBO commentator said Drury is one of the worst convention. Do you know why? (I like 4 seats drury as you do)