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Do you accept the quantitative invitation?

#21 User is offline   mw64ahw 

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Posted 2025-August-06, 00:09

One tool you can use is https://www.bridgeha...se_of_Texas.htm to determine what 4432/4333 hand you have.
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#22 User is offline   Huibertus 

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Posted 2025-August-06, 08:02

View PostCyberyeti, on 2025-August-05, 04:38, said:

I have the ability to put the cube back to partner so I bid 5N to show a decent but not stellar 16 and let partner look at his shape and intermediates and decide (yes he can have 5m).

If you put a gun to my head and said 4 or 6, I'd bid 6.


The point of my comment is NOT abut cubing back. It is to inform partner HOW to evaluate his hand BEFORE you're asking him to do so. Looking at this example hand, Q is worth a LOT more if it helps to establish a 5 card then when it helps to establish a 3 card AKX or a doubleton AK. Not informing partner of a five card before asking him to evaluate 6NT is asking partner to do the impossible. Him kicking back the question won't solve the issue. It only transfers the blame in case the pair took the wrong decision.
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#23 User is offline   Cyberyeti 

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Posted 2025-August-06, 10:01

View PostHuibertus, on 2025-August-06, 08:02, said:

The point of my comment is NOT abut cubing back. It is to inform partner HOW to evaluate his hand BEFORE you're asking him to do so. Looking at this example hand, Q is worth a LOT more if it helps to establish a 5 card then when it helps to establish a 3 card AKX or a doubleton AK. Not informing partner of a five card before asking him to evaluate 6NT is asking partner to do the impossible. Him kicking back the question won't solve the issue. It only transfers the blame in case the pair took the wrong decision.


He's already had some options to show shape, if he was particularly interested in a minor suit slam, he could have used a form of MSS, so is likely to be 33(43) good 15-16
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#24 User is offline   mike777 

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Posted 2025-August-06, 12:45

 jillybean, on 2025-August-04, 15:04, said:

First time in the club for a while, playing with a fellow Kiwi, we had a top 59% game.
No matter where I come, there are always hands to review.



MP


Interesting discussion.
I would have passed at MP and had not thought it was close before all the discussions.
Interesting...
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#25 User is offline   johnu 

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Posted 2025-August-06, 15:38

View Postpescetom, on 2025-August-05, 14:41, said:

FWIW, I dislike generic pass-back decisions after an (5NT) invite: they smack of blame-transfer (not to even mention UI opportunities).

I did some simulations a few days ago, but the site became unavailable so my post disappeared. IIRC, 6NT was in the 70% range opposite 16 HCP, but only around 50% opposite 15 HCP. Pavlicek's studies show that double dummy and actual results are relatively close for 6NT contracts with human declarers benefiting from the opening lead compared to double dummy, but doing much worse after the opening lead is made, with double dummy always getting 2 way finesses correctly, etc.

It helps to know what partner is going to bid 4NT with. 15+, 16+ ?

IMO, 5NT asks for a specific action by partner. Assuming 4NT showed 15+, Pass with 15 HCP, bid 6NT with more. An exception would be 15 HCP with a decent 5 card minor (assuming responder doesn't have a 5 card major after failing to transfer first).

No blame transfer at all since it is asking a specific question, and as for UI, 5NT already expresses doubt whether 6NT can be made.
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#26 User is offline   DavidKok 

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Posted 2025-August-07, 00:59

Having to jump three levels to invite slam is not great. Not knowing which hands partner might bid this way with is not great - I'm assuming no 4cM, 5cM, 6cm or 5m4om, but I'd really like to also rule out 5m332 and have an accurate idea of partner's strength requirements. Having our primary responses to 4NT be more jump bids is also not great - if we are accepting I think 5 is a good bid, which for me shows an accept with exactly 4 diamonds.

It's difficult to form an opinion on an auction with little bidding space, few agreements and no information on partner's tendencies.
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#27 User is offline   Huibertus 

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Posted 2025-August-07, 04:30

View PostCyberyeti, on 2025-August-06, 10:01, said:

He's already had some options to show shape, if he was particularly interested in a minor suit slam, he could have used a form of MSS, so is likely to be 33(43) good 15-16


He's already had some options to show shape. Yes of course. Which is exactly the point of my first contribution. Is he reliable at doing this?

If so pass 4NT. Or is he not so reliable in which case there's no way you can realistically assess your values and have to guess to pass 4NT or guess to bid on, both of which could be right or wrong.
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#28 User is offline   Cyberyeti 

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Posted 2025-August-07, 05:13

View PostHuibertus, on 2025-August-07, 04:30, said:

He's already had some options to show shape. Yes of course. Which is exactly the point of my first contribution. Is he reliable at doing this?

If so pass 4NT. Or is he not so reliable in which case there's no way you can realistically assess your values and have to guess to pass 4NT or guess to bid on, both of which could be right or wrong.


We play 1N-2-2-3 as MSS, similarly 1N-2-2-2 so it's pretty easy for him to find out my shape if he cares, thus the suggestion is he's 33(43)
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#29 User is offline   jillybean 

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Posted 2025-August-07, 07:36

Here's the full hand from the other thread


"And no matter what methods you play, it is essential, for anyone aspiring to learn to be a good player, to learn the importance of bidding shape properly. MikeH
"100% certain that many excellent players would disagree. This is far more about style/judgment than right vs. wrong." Fred
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#30 User is offline   eagles123 

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Posted Yesterday, 02:22

View Postjillybean, on 2025-August-07, 07:36, said:

Here's the full hand from the other thread





well 4N is just daft.
"definitely that's what I like to play when I'm playing standard - I want to be able to bid diamonds because bidding good suits is important in bridge" - Meckstroth's opinion on weak 2 diamond
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#31 User is offline   jillybean 

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Posted Yesterday, 07:24

View Posteagles123, on 2025-August-08, 02:22, said:

well 4N is just daft.

LOL I would not mind anyone calling some of my bidding daft but I'm not going tell my partner that, it's a new partnership.
He already mentioned that he could have used stayman, I do hope we discuss this hand and the 3oM treatment.
"And no matter what methods you play, it is essential, for anyone aspiring to learn to be a good player, to learn the importance of bidding shape properly. MikeH
"100% certain that many excellent players would disagree. This is far more about style/judgment than right vs. wrong." Fred
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#32 User is online   pescetom 

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Posted Yesterday, 07:30

 jillybean, on 2025-August-08, 07:12, said:

LOL I would not mind anyone calling some of my bidding daft but I'm not going tell my partner that, it's a new partnership.
He already mentioned that he could have used stayman, I do hope we discuss this hand.

Maybe he is used to weak NT? I am not, but imagine 4NT would be closer to the ball park then.
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#33 User is offline   jillybean 

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Posted Yesterday, 08:32

View Postpescetom, on 2025-August-08, 07:30, said:

Maybe he is used to weak NT? I am not, but imagine 4NT would be closer to the ball park then.

No, 15-17, you'd think a Kiwi would be used to 12-14 but we are both long time strong nt players
"And no matter what methods you play, it is essential, for anyone aspiring to learn to be a good player, to learn the importance of bidding shape properly. MikeH
"100% certain that many excellent players would disagree. This is far more about style/judgment than right vs. wrong." Fred
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#34 User is offline   gszes 

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Posted Yesterday, 10:22

IMHO --- Rules for accepting a quantitative invite (*small or grand makes no difference)
1. If your POWER is at the top of your range ACCEPT. I also subtract the value of JACKS where neither partner can have 4+ cards in that suit. The ex-hand is not at the top. look at (2)
2. If you have control HCP (A OR K) equal to the minimum of your range ACCEPT (for a 15 to 17 hand you would need at least AAAK to qualify) The ex-hand does not qualify. look at (3)
3. If you can picture a perfect hand for p to hold (and STRONG REASON to assume it can exist) that would make your slam *68%+ (the equivalent of a 32 opp card split when we have a 8 fit in a suit) ACCEPT. If p has xx(x) KQ(x) Kxx(x) AKJx. I am assuming p is either 3343 3334 2344 or 3244 and has around a 75% chance to have 4 clubs.
While p will rarely have the perfect hand but this exercise at least shows there should be a decent chance of success and it can be done QUICKLY. The ex-hand qualifies bid 6NT.

Adding some extra bids btn 4n and 6n to try for suited slams that don't qualify using the 3 above rules makes sense (more so for 6n than 7n) however these hands should be limited to hands that could not have been bid via other means earlier in the bidding. These hands will almost **always be because opener will frequently have a 5 card minor they have been unable to show. There are too many options to cover here.

*the 68% is primarily for grand slams with the 6N value greatly depending on you risk tolerance. (my risk tolerance is low so I use 68 a LOT) If you and partner feel 50% is good enough have at it.
** for the esoteric, I would use a 5h or 5s bid to show a solid (4 of top 5 not including the AKQJ) 4 card major asking if responder has a 3 card fit with and honor and a DOUBLETON in the other major.
This allows for a ruff with the short trump suit while using an honor and still allowing trumps to be drawn while catering to a 33 or 42 split.
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#35 User is online   pescetom 

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Posted Yesterday, 10:30

I wrote earlier:

View Postpescetom, on 2025-August-05, 14:41, said:

FWIW, I dislike generic pass-back decisions after an invite: they smack of blame-transfer (not to even mention UI opportunities).


But for some reason you modified this to:

View Postpescetom, on 2025-August-05, 14:41, said:

FWIW, I dislike generic pass-back decisions after an (5NT) invite: they smack of blame-transfer (not to even mention UI opportunities).


Please do not modify my quotes.

In case it was not clear, I meant literally what I wrote: I dislike pass-back decisions after any invite, not just in this specific case of a 4NT invite.


View Postjohnu, on 2025-August-06, 15:38, said:

I did some simulations a few days ago, but the site became unavailable so my post disappeared. IIRC, 6NT was in the 70% range opposite 16 HCP, but only around 50% opposite 15 HCP. Pavlicek's studies show that double dummy and actual results are relatively close for 6NT contracts with human declarers benefiting from the opening lead compared to double dummy, but doing much worse after the opening lead is made, with double dummy always getting 2 way finesses correctly, etc.

It helps to know what partner is going to bid 4NT with. 15+, 16+ ?

IMO, 5NT asks for a specific action by partner. Assuming 4NT showed 15+, Pass with 15 HCP, bid 6NT with more. An exception would be 15 HCP with a decent 5 card minor (assuming responder doesn't have a 5 card major after failing to transfer first).

No blame transfer at all since it is asking a specific question, and as for UI, 5NT already expresses doubt whether 6NT can be made.

Your argument here is not clear to me, sorry.
Your simulations and Pavlicek sound spot on, but not sure what relevance they have to the use of a pass-back or not.
Of course we have to know what we agreed to bid 4NT with, in terms of points (and any adjustment for 5 card suits, etc.).
What is the specific question that you assert the pass-back is asking?
It cannot be whether or not responder meets the agreed criteria for inviting with 4NT, they already clarified that by doing so.
Perhaps you are arguing that it should ask Responder if he is close to the agreed minimum for 4NT, effectively a split-range invite?
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#36 User is offline   johnu 

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Posted Yesterday, 17:06

View Postpescetom, on 2025-August-08, 10:30, said:

But for some reason you modified this to:


Please do not modify my quotes.

In case it was not clear, I meant literally what I wrote: I dislike pass-back decisions after any invite, not just in this specific case of a 4NT invite.

I clarified the quote to make clear I was referring specifically to the 5NT invite. Other invite cases are irrevelant to this discussion.

View Postpescetom, on 2025-August-08, 10:30, said:

Your argument here is not clear to me, sorry.
Your simulations and Pavlicek sound spot on, but not sure what relevance they have to the use of a pass-back or not.
Of course we have to know what we agreed to bid 4NT with, in terms of points (and any adjustment for 5 card suits, etc.).
What is the specific question that you assert the pass-back is asking?
It cannot be whether or not responder meets the agreed criteria for inviting with 4NT, they already clarified that by doing so.
Perhaps you are arguing that it should ask Responder if he is close to the agreed minimum for 4NT, effectively a split-range invite?

The point is that if responder can respond with a 15 HCP invite, slam is marginal. If responder has a 16 HCP invite then slam is very good. 5NT says to pass if responder has a minimum 15 HCP hand, and to bid slam with more than a minimum.

Without using 5NT (or some other 5 level bid), opener has to either pass 4NT or bid a slam without further cooperation from partner. 4NT has a range, just like 1NT. Why not ask whether the 4NT is at a minimum or not?
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#37 User is offline   johnu 

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Posted Yesterday, 19:51

View PostDavidKok, on 2025-August-07, 00:59, said:

Having to jump three levels to invite slam is not great. Not knowing which hands partner might bid this way with is not great - I'm assuming no 4cM, 5cM, 6cm or 5m4om, but I'd really like to also rule out 5m332 and have an accurate idea of partner's strength requirements. Having our primary responses to 4NT be more jump bids is also not great - if we are accepting I think 5 is a good bid, which for me shows an accept with exactly 4 diamonds.

It's difficult to form an opinion on an auction with little bidding space, few agreements and no information on partner's tendencies.

George Rosenkranz invented a convention called CONFI which was published in the Bridge World. This was designed to find a suit fit between 2 balanced hands after a NT opening bid when HCP was marginal for 6NT.

The main concepts of the system were:

1. You usually need 10 controls (ace = 2, king = 1) with 2 balanced hands, otherwise slam will usually be on a finesse or worse. Reasoning: If you have 9 controls, you are missing an ace and a king. The ace is a sure loser, the king probably has to be picked up with a finesse, so no better than 50%, unless the ace and king are in the same hand, in which case, the opponents may lead AK on the opening lead, or if you can't make 12 immediate tricks, have to concede tricks to the ace and king.
If you are missing 3 kings, you need to get 2 out of 3 finesses right, so no better than 50%.

2. A 4-4 (or possible 5-4, or more rarely a 5-3 fit) may produce an extra trick through ruffing. So the 2nd goal of CONFI is to find a 4-4 fit (or better).

3. A weak 4-4 fit can introduce an extra loser (or 2 with a bad trump split), offsetting the advantage of a 4-4 fit in 2) above. So an emphasis is finding a strong trump suit, holding the top 3 honors, or missing only the ace or king.

4. With enough HCP, 6NT becomes the favorite over 6 of a suit because it can frequently overcome a 4-1 or 5-0 split in a possible trump suit, or risk a ruff.

The problem is that this has some complexity, which is a major problem for inexperienced partnerships, and it's best started at a low level, which conflicts with using that bid for another purpose.
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