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4D as natural DCB...

#1 User is offline   foobar 

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Posted 2022-January-03, 18:57

The SCAMP book proposes an interesting "natural DCB" alternative to the terminator puppet 4 (with optional RKC). The gist of the method is that after shape is resolved, bidding 4 is a mild-slam try (MST), that asks the responder to scan suits in natural order, i.e., ///.

So, assuming an auction that resolves 6421 shape at say 3, 4 starts the MST in an undefined suit:

....4: Either bad hearts, or any minimum hand (< base+2 QPs and < 3 controls)
....4: Good , bad
....4N: Base+4 QPs
....5: Good /, bad
....5: Good //

Note that this can be used after a QP ask as well. A description of the method can be found here: https://nick-coleta....ary-20d-Apr.pdf


This seems to be a very interesting method, and has anyone tried it?
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#2 User is offline   straube 

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Posted 2022-January-04, 03:23

4D non-step after shape resolved is a mild slam try
.....4H-all minimimums
.....4N-4+ QPs (if unlimited)
.....other shows something extra, perhaps 2 or 3 QPs or an extra control and names "bad" trump suits upwards

"bad" = worse than Qx(x) or HHxx(X)

If 4D comes after a QP answer then suit quality is the only issue. (4N unused apparently)

...............................................................................................................
When would they use this? My guess is that in practice they only use it after the slave hand has reached 3S or 3N because even a minimum hand would choose the QP ask at a pattern resolution of 3H or lower. So let's assume pattern shown at 3S. Now 4C is QP ask and 4D is the mild slam try. If pd bids 4N we know 4+ QPs but now we have to resolve QPs at a high level. If pard bids 4H we have a straightforward pass or correct. If pd bids a suit (btw partner never bids shortness is that right?), we have some information that may be useful, but how do we continue? Any suit bid would be a correction presumably so captain just places the contract.

At pattern resolution of 3S or 3N I liked....

4C-QP ask
.....4D-base or base+1
..........4H-ask
4D-QP ask, weaker
.....4H-base or base+1
..........P/C
4H-to play
.....4S-4 QPs
.....etc
4S-to play
.....4N-4 QPs
......etc

which let me fish for +2 QPs for hearts, +2 or +3 for spades, and use parity cue bids pretty much always.
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#3 User is online   awm 

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Posted 2022-January-04, 05:28

It seems like there should be a way to sign off in 4 without risking that partner bids on with mild extras. Without such a method, it seems like you risk getting to 5 on very marginal hands way too often.

I suppose in this method the idea is that 4 is a signoff (barring Base+4SP). In this case we've swapped the "mild slam try" hands between bidding game and the 4 call. It seems to me that it's better to have:

4 = sign off barring Base+4SP
4 = mild slam try in

rather than

4 = mild slam try in some suit, paradox responses
4 = sign off barring Base+4SP

The reasoning is that you can get a lot more useful information out of partner when he has a possible accept of the mild slam try. For example, suppose partner has a nice hand for hearts. Whether he bids 4 or 5 or 5 in SCAMP seems not super-useful -- I'm not sure how this helps you judge whether to try 6 or not (beyond the "not super-min, nice hand for hearts" information). Whereas in the more standard method he can respond to 4 by showing keycards or even revert to DCB, so you know "nice hand for hearts, X number of keycards/control" which seems much more powerful.
Adam W. Meyerson
a.k.a. Appeal Without Merit
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#4 User is offline   foobar 

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Posted 2022-January-04, 12:26

 awm, on 2022-January-04, 05:28, said:

It seems like there should be a way to sign off in 4 without risking that partner bids on with mild extras. Without such a method, it seems like you risk getting to 5 on very marginal hands way too often.

I suppose in this method the idea is that 4 is a signoff (barring Base+4SP). In this case we've swapped the "mild slam try" hands between bidding game and the 4 call. It seems to me that it's better to have:

4 = sign off barring Base+4SP
4 = mild slam try in

rather than

4 = mild slam try in some suit, paradox responses
4 = sign off barring Base+4SP

The reasoning is that you can get a lot more useful information out of partner when he has a possible accept of the mild slam try. For example, suppose partner has a nice hand for hearts. Whether he bids 4 or 5 or 5 in SCAMP seems not super-useful -- I'm not sure how this helps you judge whether to try 6 or not (beyond the "not super-min, nice hand for hearts" information). Whereas in the more standard method he can respond to 4 by showing keycards or even revert to DCB, so you know "nice hand for hearts, X number of keycards/control" which seems much more powerful.


Here's the example hand provided for the method.


AQxx Jxx xx AQxx (responder)
Kx AKxxx KQxxx K (RC)

After 3N showing 8 QPs with 4=3=2=4, 4 is the MST:


...4: Bad , so all pass

Under DCB/PCB, we will scan in the -- order, meaning we'll perforce end up at 5. Granted, 5 rolls home comfortably as well in this case.

Another example was:


Kxx KQxxxx Kxx x (responder)
Axx Axx Ax KQxxx (RC)

After 3 showing 3=6=3=1, 4 is the MST, then:
...5: Good , , bad
-
DCB/PCB will first go through QP ask (3), then infer the same information, albeit via the -- scan, so it looks like a wash.

Another (somewhat contrived) example after 3N showing 3=3=0=7:

xxx Axx void KJTxxx (responder)
AKxx KQx Axxxx Q (RC)

....4 (MST): Good , bad

Now 5 is an invitation and responder accepts with good trump.

I suppose on the last example, straube's weak 4 QP ask might work to the same effect.
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#5 User is offline   foobar 

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Posted 2022-January-04, 12:27

 straube, on 2022-January-04, 03:23, said:


At pattern resolution of 3S or 3N I liked....

4C-QP ask
.....4D-base or base+1
..........4H-ask
4D-QP ask, weaker
.....4H-base or base+1
..........P/C
4H-to play
.....4S-4 QPs
.....etc
4S-to play
.....4N-4 QPs
......etc

which let me fish for +2 QPs for hearts, +2 or +3 for spades, and use parity cue bids pretty much always.


This looks interesting -- see the last example in my other post.
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#6 User is offline   straube 

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Posted 2022-January-04, 20:20

 foobar, on 2022-January-04, 12:26, said:

xxx Axx void KJTxxx (responder)
AKxx KQx Axxxx Q (RC)


That's a really tough target. As asker, I'd be worried about which game had the best chance.

I think having the invitational QP ask is useful a high percentage of the time. And I have 5C+ that I could assign for trump solidity asks if I wanted....
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#7 User is offline   DinDIP 

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Posted 2022-January-18, 05:20

Adam is right that this is a swap: instead of using 4 as an end signal with game bids as NAT slam tries, focusing on trump strength, game bids are to play and 4 asks across all suits.

This came about when Nick and I played together in 2008 in a qualifying event for the Australian team selection trials. In 1982-84 we were a regular FP symmetric partnership but my moves interstate and overseas for work meant we didn't play together for a decade and then only once or twice a year. We were also often playing as part of a team where we all played SCAMP (strong club) or SPAM (FP). Nick's regular partner had a high propensity to forget that game bids were slam tries so we never adopted 4 as an end signal. Frustrated by our inability to sort out suit-quality issues I suggested using 4 to ask in all suits as it was otherwise reserved for asking for aces (mostly).

Over time we discovered that the bid solved a number of problems, including when shape is resolved at 3 or 3N. This includes auctions after a semipos response to a 1 relay when we are +2. It's not perfect and, as Adam notes, more useful information can be conveyed if a suit is set. Things can also get tricky when teller has a super-positive but a weak holding in the suit asker is interested in; 4N is reserved for those hands but it's still awkward to sort out strain and ascertain if the grand is worth bidding.

However, if you have no other way in your system of ascertaining suit quality, especially when teller has a long suit, then it's a tool worth considering. I used in some of the hands that Richard or David put forward years ago to compare methods (see for example https://www.bridgeba...__1#entry793510) and also discussed it in passing in https://www.bridgeba..._1#entry858293. I thought I had also written a separate article about it in this forum but I can't easily find it.
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#8 User is offline   straube 

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Posted 2022-January-18, 10:08

If you can't have both, I think it's better to have a general invite instead of an invite that focuses on trump quality. I had a lot of personal bidding practice success using both 4C and 4D as QP asks and surprised that there hasn't been much interest in it.
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#9 User is offline   pilun 

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Posted 2022-January-19, 17:47

In devising our symmetric method, the twin aims were simplicity and consistency.
So non-step game bids are to play.
What we didn't want is RRRR-game = sign-off, while RRRRR-game is a slam try or (heaven forbid) RKC in suit Z.

Our basic DCB is quite crude but seems to go okay.
Still, 4 non-step was idle and - as per David's suggestion - we decided to find a use for it.
We chose "My next bid will be natural slam try, requiring "extras" including "good" trumps."

It's still a bit vague.
"Extras" is +2 SPs or maybe +1 kontrols, unless that has already been shown.
"Good" trumps were 2 of top 3 (or maybe 3 of top 4) in 4+ suits, one of top 3 in shorter suits.

Here is a hand from this week.



Partner's shape and strength was a disappointment. The most likely spread of top honours is the actual, minus Q. (We neither count for stiff queens, nor show them in DCB). Slam is no good. KQxxxx, x, KQxx, xx would be even worse.

K is odds against and looking for it might take us to a failing 5.
I was about to sign off in 4 then started wondering whether partner might have the stiff Q. 4 couldn't cost. (Partner had already bid hearts first)

4 - 5 = "good majors", no club honour.

I could have passed the buck with 5 but I was so chuffed about finding the Q, that I bid 6, which partner played well to make.


The bad hands for DCB are those with honours sprinkled over three or four suits. Not only are these hands less useful for slam, showing them chews up a lot of space and can take you overboard. We've had poor auctions like

4 - 5 = "I've got honours everywhere!"

"Thanks a lot. Not happy."

More often, concentrations of strength are required. Here is another hand from this week.



The field had no real problems reaching 6, often after West made a Jacoby raise. It's usually wrong to relay with a good trump fit and a shortage but we had no choice. (2NT over 1 would be a limit+ HEART raise) After East's 3, West was stuck with asks, not shows.

Slam is good opposite the actual, chunky East hand but not opposite any hand with a diamond honour or one with poor trumps. Even
QJxxx, AKxx, xxx, x is not enough. Hence 4:

4 - 4 (hearts not quite good enough)
4 - 5 = two top spades plus A.
6

It turns out that 4 DCB would have been okay.
4 - 4 = , , no honour
Though 4 could equally land us in 5 opposite
KJxxx, Jxxx, AQx, x. Yuk!

While you are here, how would you play 6/E on the actual, after a diamond to the ace and a heart back?
I guess you rise ace, K-A. If trumps are 2-2, hope clubs are 4-3 or short J.
If trumps are 3-1, perhaps draw the last trump then finesse the 10?
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#10 User is offline   foobar 

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Posted 2022-January-19, 19:07

 pilun, on 2022-January-19, 17:47, said:


....


Partner's shape and strength was a disappointment. The most likely spread of top honours is the actual, minus Q. (We neither count for stiff queens, nor show them in DCB). Slam is no good. KQxxxx, x, KQxx, xx would be even worse.

K is odds against and looking for it might take us to a failing 5.
I was about to sign off in 4 then started wondering whether partner might have the stiff Q. 4 couldn't cost. (Partner had already bid hearts first)

4 - 5 = "good majors", no club honour.

I could have passed the buck with 5 but I was so chuffed about finding the Q, that I bid 6, which partner played well to make.


....
Slam is good opposite the actual, chunky East hand but not opposite any hand with a diamond honour or one with poor trumps. Even
QJxxx, AKxx, xxx, x is not enough. Hence 4:

4 - 4 (hearts not quite good enough)
4 - 5 = two top spades plus A.
6



This is slightly confusing. In the first case, responder showed good majors with the stiff HQ, but in the second case, AJxx is deemed as "not good enough"?
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#11 User is offline   DinDIP 

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Posted 2022-January-19, 23:08

 straube, on 2022-January-04, 03:23, said:

At pattern resolution of 3S or 3N I liked....

4C-QP ask
.....4D-base or base+1
..........4H-ask
4D-QP ask, weaker
.....4H-base or base+1
..........P/C

which let me fish for +2 QPs for hearts, +2 or +3 for spades, and use parity cue bids pretty much always.


Interesting idea, David. Aren't you limited to fishing for +2 in both majors? If you need +3 in spades then you have to guess which ask to use: if you ask with 4 then you can't play 4 when teller is +2, and if you ask with 4 then you can't signoff in 4 if teller has base or base+1.
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#12 User is offline   DinDIP 

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Posted 2022-January-19, 23:33

 foobar, on 2022-January-19, 19:07, said:

This is slightly confusing. In the first case, responder showed good majors with the stiff HQ, but in the second case, AJxx is deemed as "not good enough"?


My guidelines are:
* Assume an 8 card fit
* Accept with
- (if you have 1-2 cards) 1 of the top 3 honours
- (if 3-5 cards) 1 loser opposite one of the top 4 honours
- (if 6+ cards) 1 loser opposite small cards

David
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#13 User is offline   straube 

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Posted 2022-January-20, 00:08

 DinDIP, on 2022-January-19, 23:08, said:

Interesting idea, David. Aren't you limited to fishing for +2 in both majors? If you need +3 in spades then you have to guess which ask to use: if you ask with 4 then you can't play 4 when teller is +2, and if you ask with 4 then you can't signoff in 4 if teller has base or base+1.


Hi David. No, this method specifically you to look specifically for +3 in spades (i.e. +2 won't do). If I need +3 for spades, I use the 4D ask because it denies interest in base 0 or base +1.

4D-asks
.....4H-base or base +1
..........P-I was looking for base +2 or better
..........4S-sign off (I was looking for base +2 or better)
.....4S-base +2
..........P-I was looking for base +3
.....4N-base +3

This use of 4D is of course used just to ferret out QP holdings when asker may want to sign off in 4M because the 4C ask saves room while allowing for a sign off in 5m.

A side benefit of this scheme is that we flow directly into denial cue bidding so we don't have to have a separate (arguably worse) continuation.
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#14 User is offline   foobar 

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Posted 2022-January-20, 00:29

 straube, on 2022-January-20, 00:08, said:

Hi David. No, this method specifically you to look specifically for +3 in spades (i.e. +2 won't do). If I need +3 for spades, I use the 4D ask because it denies interest in base 0 or base +1.

4D-asks
.....4H-base or base +1
..........P-I was looking for base +2 or better
..........4S-sign off (I was looking for base +2 or better)
.....4S-base +2
..........P-I was looking for base +3
.....4N-base +3

This use of 4D is of course used just to ferret out QP holdings when asker may want to sign off in 4M because the 4C ask saves room while allowing for a sign off in 5m.

A side benefit of this scheme is that we flow directly into denial cue bidding so we don't have to have a separate (arguably worse) continuation.

Think this works only when QPs are capped, right (read IMPrecision)? For example, 4N shows base+3, which won't work opposite an unlimited responder?
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#15 User is offline   pilun 

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Posted 2022-January-20, 05:53

 foobar, on 2022-January-19, 19:07, said:

This is slightly confusing. In the first case, responder showed good majors with the stiff HQ, but in the second case, AJxx is deemed as "not good enough"?


You just need to accept that you will pick up some suit combinations but not others.
Holding Qxxx, you may want partner to go on with KJxx and AJxx for one loser most of the time, so maybe that's enough if everything else looks solid.

On the other hand, you may want a trump suit to play for no losers. In that case
Qxxx, needs AKxx, Kxxx needs AQxx, etc.

Respond might feel like accepting with AJTx, though that could be slam on a finesse.

With singletons, stiff queen is as good as it gets when SPs are known.
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#16 User is offline   straube 

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Posted 2022-January-20, 09:34

 foobar, on 2022-January-20, 00:29, said:

Think this works only when QPs are capped, right (read IMPrecision)? For example, 4N shows base+3, which won't work opposite an unlimited responder?


No. 5C=base +4, 5D=base +5 etc

With this, you divide asker into 3 tiers...
.....1) weak, you sign off in 3N or 4M and the slave hand resurrects only with 4+ QPS
.....2) strong (or any if the destination is 5m since you have room)
.....3) intermediate with interest in a 4M contract (bid 4D)
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