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Jacoby 2S/2NT variations On the cusp

#21 User is online   mw64ahw 

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Posted 2021-September-06, 08:59

If you're behind in the 4th quarter (no prizes for 2nd) and want to bid the slam - I've been experimenting with this strength based Lim+,3+ approach using ideas from the web
The mechanics are straightforward once a hand has been classified into Lim,LimX,Min,MinX,Int,IntX,Str+. Initial classification is based on an hcp range defined versus an unbalanced/balanced hand.
The T&P Jacoby 2/2NT (T&P = Tried & Played although mostly many simulated hands, but it has worked well in actual play)

After 1-2 bid increments are based on strength
2NT +1 Min
3 +2 MinX
3 +3 Int
3 +4 IntX
3-4 5+ Str+ ITL Q Bids
Following the first step responder may be able to place the contract or move to slam investigation after hand revaluation. If not responder shows shows his strength based on MLT/TP. For example when opener is Min.


After 1-2--2NT
3 7.5MLT or lower MLT/TP equivalent
3 8MLT or lower MLT/12TP
3 >8 MLT/10-11TP
This time opener may be able to place the contract depending on revalued strength.


After 1-2--2NT-3
3 8MLT (i.e. a balanced minimum)
3 6.5.MLT/15-16TP 2+KCs/1KC & Q trumps
3-4 6 or lower MLT/17+TP 2+KCs/1KC & Q trumps
4 anything else.

After 3/an Italian Q bid responder can place the contract or continue slam investigation.

I'm still simulating the optimal revalued TP ranges to combine with the MLT so the above are initial indications

The advantage of this approach is that the contract can often be placed in 3/4M with little clue being given as to what to lead. I tend not to use the approach when I have an alternative 5+ card suit and a 3 card trump suit without honours and enough for a 2/1 bid.

The way to a slam (and yes it depends on the K sitting with West) via the
T&P Jacoby 2/2NT
Italian Q bids
Kickbo

2 (3+, Limit+)
2NT (Min)
3 (Min+ MLT/revalued TP based)
3 (ctrl, 6 or lower MLT/17+TP w. at least 1 honour & 2KC/1KC & Q)
4 (ctrl & honour since 3NT is bypassed)
4 (no ctrl)
5 (AK,ctrl & 3/5 KCs)
6 (5 of 6 keycards)


Comments/questions welcomed.
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#22 User is offline   Gilithin 

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Posted 2021-September-06, 10:09

View Postmw64ahw, on 2021-September-06, 08:59, said:

Comments/questions welcomed.

I would fairly strongly recommend that you make your first 2 steps min/int with shortage rather than the first 2 being min and divided by shape. Balanced and semi-balanced hands need less room to show salient features than unbalanced hands with a shortage so you want the latter to be shown as cheaply as possible. If you really want the first step to be (semi-)balanced then it is probably better not to include a range at all and have Responder describe their hand instead, thus allowing min/int hands with shortages to take steps 2 and 3.
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#23 User is online   mw64ahw 

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Posted 2021-September-06, 10:33

View PostGilithin, on 2021-September-06, 10:09, said:

I would fairly strongly recommend that you make your first 2 steps min/int with shortage rather than the first 2 being min and divided by shape. Balanced and semi-balanced hands need less room to show salient features than unbalanced hands with a shortage so you want the latter to be shown as cheaply as possible. If you really want the first step to be (semi-)balanced then it is probably better not to include a range at all and have Responder describe their hand instead, thus allowing min/int hands with shortages to take steps 2 and 3.

Thanks for the comment
I've tried this similar approach Modified Jacoby 2NT - Bridge Articles - Bridge with Larry Cohen, but found that partner struggled to remember the various options.
This strength only based approach in its simplest granular form relies on basic MLT addition to reach a suitable contract. Naturally playing strength is affected by card distribution, but this approach is ambivalent about shape, apart from knowing that there is an 8 card fit.
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#24 User is offline   HardVector 

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Posted 2021-September-08, 13:28

View Postmw64ahw, on 2021-September-05, 06:06, said:

This one is a close call, but as it stands I end in 4 without a slam investigation. When its close to 50% I at least like to make the investigation. Im wondering if there is any scientific approach that at least gets you to the investigation stage.

There is a way to investigate, but it would probably involve playing some other system than 2/1. For instance, I am currently playing GUS which is a relay system. We would have bid it as follows:

1h (11-15, unbalanced) - 2c (GF, relay)
2n ("bad" 6/4 hand) - 3c (relay)
3n (6 hearts/4 spades, shortness in clubs)

This hand I judge to be bad because of all the soft honors plus the dubious diamond Q. The relayer doesn't care, however, and finds out about the spades. The bad descriptor may cause no further exploration here, but if they should continue, they would find out about the missing heart A and spade K and stop. The minors are covered, but the majors are a problem.

I am sure there are other systems out there that could do this as well, but it involves the ability for someone to take charge. Jacoby attempts that, but the information you gain is limited to just shortness or 5/5 and 6/5 descriptors.
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#25 User is online   mw64ahw 

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Posted 2021-September-08, 14:06

View PostHardVector, on 2021-September-08, 13:28, said:

There is a way to investigate, but it would probably involve playing some other system than 2/1. For instance, I am currently playing GUS which is a relay system. We would have bid it as follows:

1h (11-15, unbalanced) - 2c (GF, relay)
2n ("bad" 6/4 hand) - 3c (relay)
3n (6 hearts/4 spades, shortness in clubs)

This hand I judge to be bad because of all the soft honors plus the dubious diamond Q. The relayer doesn't care, however, and finds out about the spades. The bad descriptor may cause no further exploration here, but if they should continue, they would find out about the missing heart A and spade K and stop. The minors are covered, but the majors are a problem.

I am sure there are other systems out there that could do this as well, but it involves the ability for someone to take charge. Jacoby attempts that, but the information you gain is limited to just shortness or 5/5 and 6/5 descriptors.

Thanks another system for me to investigate when I get round to buying the book.
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#26 User is offline   HardVector 

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Posted 2021-September-08, 19:40

View Postmw64ahw, on 2021-September-08, 14:06, said:

Thanks another system for me to investigate when I get round to buying the book.

Book(let)s..plural. There are 8 of them. The good news, is that it's designed to implement piecemeal, so you don't have to memorize the whole thing in one shot.
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