[euclidz]

Where can I find some free on-line reading that will convince me that RKCB is of value for the average or even better than average Club player?

Why do I ask . . . I feel like I should have it on my card but I REALLY can't see it being of any value other than the 1 in 10,000 occasions when I think there is a Grand Slam on in a suit. I can't see it of any value when the I'm looking at a NT slam, in fact I can't see how it works when a suit has not been agreed and we're in NT's.

All that said . . . point me to a write-up somewhere that will convince me I should have it?

[Cyberyeti]

What are you playing instead ? standard Blackwood ? 5-ace ?

[euclidz]

Cyberyeti, on 2023-April-28, 06:19, said:

What are you playing instead ? standard Blackwood ? 5-ace ?

With my Club partner we play Gerber if Clubs have not been bid and standard Blackwood if Clubs have been bid. Gerber is good for keeping it low if we need to get out and Blackwood is what it is. I've been playing Bridge for 40 years and I have come across many players belive that the greater the number and more complex the conventions on their car is a testiment to their ability. All that said, I play on-line and most other play RKCB and I am happy to learn it if I can find some reading that will convince me it will add value to find 12 trick slams.

[DavidKok]

In 6-of-a-suit the king of trumps is arguably as important for maintaining control of the hand as any ace, and it will likely have to be knocked out early if you do not have it. Furthermore, unless you have a favourable finesse, it is an unavoidable loser. That is the main argument for using RKC.

I think ace-asking or keycard-asking bids in general are overrated, and you may almost as well do away with most of them. Not much is gained or lost by swapping out one version for a different one.

[Cyberyeti]

euclidz, on 2023-April-28, 06:33, said:

With my Club partner we play Gerber if Clubs have not been bid and standard Blackwood if Clubs have been bid. Gerber is good for keeping it low if we need to get out and Blackwood is what it is. I've been playing Bridge for 40 years and I have come across many players belive that the greater the number and more complex the conventions on their car is a testiment to their ability. All that said, I play on-line and most other play RKCB and I am happy to learn it if I can find some reading that will convince me it will add value to find 12 trick slams.

Well it keeps you out of small slams where you're missing an ace and the trump K, if you don't bid those anyway, you will miss a lot of good slams when you do have the trump K, if you do tand to bid them, you'll be missing the trump J some of the time also.

[AL78]

The trump king can be as important as any ace for the purpose of deciding whether or not slam is on, and knowing about the trump queen can make the difference between a small and a grand slam. If you play the 5NT followup as asking for specific kings that can give you better information on how well the two hands gel and can make the difference between judging whether to bid a small or grand slam.

AIUI, if a suit hasn't been agreed, 4NT is often treated as quantitative, or it will be implicitly agreeing a suit that has been bid strongly by one of the partnership.

Having said all that I don't think it matters much for average club players if at all what flavour of Blackwood you play. In my experience it comes up once or twice a year and when it does come up, it won't always matter what version you are playing, you'll get to the same contract.

[Stephen Tu]

It might help if you realize that it's not to "find" 12 trick slams. It's to stay out of them! It's not a slam try, as many club players misuse it (and reg blackwood and reg Gerber); it's "I already have high confidence from prior bidding that we have sufficient power/fitting distribution to take 12 tricks + not 2 fast losers in any side suits, but I am just double-checking we aren't off two key cards". These are situations where if you did not have the tool, and your only choices were to bid game or bid six, you'd guess to bid six. But you have the tool, and are trying to cut out bidding six on the ones that are low percentage because of poor trumps, which can be hard to diagnose because most systems don't focus on that in the earlier auction since the only criteria is usually just combined length on most sequences.

You really do not want to be off one ace + the K of trumps. In the best case scenario, you have QJT of trumps and it's approx on a hook in trumps. But even those, those are below par, because the opps might have say ace and a ruff if a side suit breaks badly, bringing it slightly below the 50% you need to break even (at either MPS or IMPS). And if you are missing any of Q/J/T, it's much worse, now you need trump K onside, plus maybe a 3-2 trump break, or need both KT onside, or need Kx onside exactly, etc. Or you are missing say K and J and an ace and have zero play. Similar argument, to a lesser extent, applies to missing a key + Q of trumps where in the long run overall you do not want to be in those slams either (although a few you do in retrospect, like slams where the only issue is being off trump KQ with AJT9x vs xxxx, where keycard bidders would avoid but non-kc bidders might bid it)


Gerber - other than a few fairly defined sequences, that seem to crop up only once every few years depending on frequency of play, close to 100% of experts do not use it as the common club players who trot it out routinely. 4c is far too valuable to use to show control in clubs or shortness in clubs to give it up for ace asking, you are bidding it when you are still unsure of the power and mesh of the hands for 12 tricks to be there, before you worry about being off two aces, or ace + K trumps, or keycard + Q of trumps.

[mycroft]

The "average" club player bids 4NT to tell partner "we might have slam". And they like 4♣ Gerber over suits because they can pass the message and still get out at the 4 level.

For them, Keycard has zero added value.

For the pairs that have learned that ace-asking is a way to stay out of bad slams (and have other ways to investigate slam that can work out if there are 12 tricks, or two *quick* losers in one suit), Keycard is incredibly useful, for all the reasons others have mentioned (the trump K is almost as important as an Ace when looking at "do we have two losers", and you can frequently also find out about the trump Q - which is almost as important, especially in an 8-card fit, as the A or K, ...)

But they first have to be able to use the information from partner's response, whether that be straight-Ace or Keycard.

Apologies if it looks like I'm denigrating the "average" club player. But we all know these pairs exist, and not just on the low end. I am reminded of the (apocryphal?) court transcript: "I am not a good bridge player. I am a bad bridge player. It's just that everyone else is worse than I am." If so, how bad am I, and how much worse is the average club player?

[euclidz]

Reading the responses to my post seems to confirm one of the points I put forward and that RKCB is only of any value when a suit is agreed . . . . apart from having no value in NT slam contract I would like to know (if anyone could point me to a piece of reading) what the RKCB bidders bid when there in no suit agreed; as the RKCB response bids all indicate K and Q key cards in an agrred suit what is bid when a suit has not been agreed?

[mycroft]

If not suit agreed, default is last bid suit, or strong hand (2♣ opener's) suit, or "if no suit agreement, it's straight ace". Pick a default, agree it with partner, it literally doesn't matter what it is [*] except that whatever you pick, you'll have wanted a different default on one or two hands a year.

Obviously KeyCard is less useful in NT auctions - that's why 4♣ Gerber (over NT) usually isn't keycard. But any auction that finds a long-suit fit needs to know if they have slow losers in that suit (you know, the K and Q?), and many of them, especially when the fit is a minor, or at matchpoints, will be looking to bid slam in NT. Just because you decide to keycard doesn't mean you're not planning on NT from round 1 - frankly, sometimes the difference between slam in the suit and in NT is knowing if the "trump suit" is going to run for no losers!

So, 100% not "no value in NT slam [investigation]".

[*]Okay, I know of some pairs for whom 2♣-2♦; 4NT is keycard for diamonds. Sure, but "last bid suit, even if it's totally artificial" is at least better than no agreement.

[DavidKok]

In most auctions without a fit it is more important to show the strength of the hands, rather than ask for aces. I'd usually make quantitative bids in that case, or sometimes set a dummy suit as trumps to return to 6NT later (and benefit from the extra knowledge in a long suit for a source of tricks along the way). I'm honestly not sure that this is a problem that comes up at all. Could you give an example auction?

[mycroft]

We have someone local who's done some double-dummy analysis that says with 2 balanced hands, 31 HCP is odds on (like 2-1 DD) for slam. Probably even more odds on if you've checked with Gerber to ensure that 8 of those missing 9 HCP aren't two aces...

[thepossum]

There have been many occasions where I felt second round or RKCB was problematic and I would have preferred a simple King count
I was brought up on standard which is still simpler and less error prone - but am happy looking for the King and Queen of trumps
One other problem - there are a few sequences where RKCB seems to push you unnecessarily too high - maybe that's just how it is incorrectly used by some

I am curious though at players trying for slam when a suit hasn't been agreed - that is an area of Bridge I have missed to date - perhpas you mean that the person asking has found a good fit with slam prospects but you are unhappy at their choice

[Stephen Tu]

euclidz, on 2023-April-28, 11:34, said:

Reading the responses to my post seems to confirm one of the points I put forward and that RKCB is only of any value when a suit is agreed . . . . apart from having no value in NT slam contract I would like to know (if anyone could point me to a piece of reading) what the RKCB bidders bid when there in no suit agreed; as the RKCB response bids all indicate K and Q key cards in an agrred suit what is bid when a suit has not been agreed?

If a suit has not yet been agreed, typically 4nt should just be a quantitative invite. Partner either passes or bids 6nt (or maybe 6 of his own suit if it is solid).
With some possible exceptions where partner has shown a strong single suiter in a major at the 3 level where it's not possible to agree M then kc (since 4M would be to play), where you can agree 4nt is RKC for the major.

[DavidKok]

mycroft, on 2023-April-28, 15:11, said:

We have someone local who's done some double-dummy analysis that says with 2 balanced hands, 31 HCP is odds on (like 2-1 DD) for slam. Probably even more odds on if you've checked with Gerber to ensure that 8 of those missing 9 HCP aren't two aces...

Yes, double dummy frequently does a trick better with high HCP than human declarers. It will always find the offside queens, take the right finesses and play for the only correct squeeze. I recently ran some simulations on the converse question (not 'how many HCP do we need for slam to be good', but, 'given that we have slam, what is our average HCP?'). For 6-of-a-suit the answer was 25.9 (range from 17 to 33), for 6NT the answer was 29.3 (range from 21 to 36). Other than some interesting observations on conditional probabilities and tails of the HCP distribution my primary conclusion is that double dummy gets an unfair advantage in the slam zone.

[euclidz]

I have scoured the internet and have found NOTHING that discusses the question of the value or what to do when playing RKCB when no suit has been agreed and the bidding goes along the lines of 2C / 2D / 2NT ??? I have read here, above, various suggestions on what a pair might choose to agree to do in those circumstances but I can't believe that this system, so widely used does not have definitive answers for the 'no suit agred' route.

The problem (in my experience) with standard blackwood (with no agreed suit) is that once 4NT is bid there is no exit route and 6NT is inevitable. Gerber (again in my experience) is simple and effective to get there or get out or better still Gerber and Blackwood (4C follwoed by 4NT) but 99% of players on BBO do not play Gerber and WILL NOT play Gerber . . . is that some kind of snobery i.e. better players don't play Gerber or is there any sound reasons why Gerber is a poor tool?

[smerriman]

euclidz, on 2023-April-29, 03:03, said:

I have scoured the internet and have found NOTHING that discusses the question of the value or what to do when playing RKCB when no suit has been agreed and the bidding goes along the lines of 2C / 2D / 2NT ???

That's because there are virtually zero hands where all you need to know after that auction is how many aces partner holds, so what ace-asking system you play isn't really relevant. Bids (including 4NT, which is definitely not asking for aces even if playing any form of Blackwood) are used to share other more important information instead.

[Stephen Tu]

euclidz, on 2023-April-29, 03:03, said:

I have scoured the internet and have found NOTHING that discusses the question of the value or what to do when playing RKCB when no suit has been agreed and the bidding goes along the lines of 2C / 2D / 2NT ??? I have read here, above, various suggestions on what a pair might choose to agree to do in those circumstances but I can't believe that this system, so widely used does not have definitive answers for the 'no suit agred' route.

That's because people never use RKC directly after 2c-2d-2nt without setting a suit first. It's inapplicable when a trump suit hasn't been set, 2nt-4nt and 2c-2d-2nt-4nt are absolutely never RKC.

After 2c-2d-2nt, or 2nt-?, normally 4nt is played as a quantitative invite (bid 6 if max, pass with min, advanced partnerships may have methods to accept but also look for say a 4-4 minor or 5-3/6-3 minor fit also). 2nt - 4c is Gerber for a lot of players here, at least in countries where South African Texas is unpopular. Though some might prefer 4c to be part of set of bids to find minor suit slams (perhaps just showing long clubs).

But it's quite rare to be dealt hands where you just want to have partner answer aces and then you can just count tricks and place the contract. So it's far more common over 2nt to search for a suit fit first, or to set a suit first then use keycard/kickback/minorwood/optional minorwood (e.g. texas transfer then 4nt, 2nt-3S! (puppet to 3nt)-3nt-4c/4d showing a minor one suiter)
Gerber is more useful when your suit is solid like KQJTxx and you aren't missing K or Q of your suit, or you are going to chance it on power (~32+ hcp) but don't want to be off 2 aces.

Or on some hands, you might start with stayman and then set a trump suit, then RKC (2nt-3c-3H-3s! (setting hearts by bidding other major)-?-4nt). Or one might jacoby transfer at 3 level and show a 2nd suit, then RKC if opener shows fit for the major. Or you might be playing GF jacoby transfers and know right away if opener has a major fit or not (if they only accept with 3, your system not catering to very weak hands being able to sign off in 3M opposite 2 only), then RKC.

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The problem (in my experience) with standard blackwood (with no agreed suit) is that once 4NT is bid there is no exit route and 6NT is inevitable.

Only with beginner level players (or "permanent beginners") who have never learned about quantitative invites over natural NTs (or otherwise when no suit has been agreed) where one is supposed to treat 4nt as natural and pass it frequently.

Quote

Gerber (again in my experience) is simple and effective to get there or get out or better still Gerber and Blackwood (4C follwoed by 4NT) but 99% of players on BBO do not play Gerber and WILL NOT play Gerber . . . is that some kind of snobery i.e. better players don't play Gerber or is there any sound reasons why Gerber is a poor tool?

Gerber is fine over 2nt if you have the hand for it, it just very rarely comes up. The main thing is sequences like 2nt-3h!-3s-4c should not be Gerber (what if you have a good hand with spades and clubs, you want to find slam in either suit, you need 4c natural; if you just want to rkc in spades just bid 2nt-4h!-4s-4nt, if you just want to ask aces then 2nt-4c!). Or 2nt-3c-3h-4c should also not be Gerber (you have 4 spades 5 clubs or 4 spades 6 clubs, want to explore slam in either suit).

Basically Gerber is fine as a direct bid over 1nt/2nt/natural 2nt rebids, but if you are looking for suit slams and need to be able to bid clubs naturally or to show control in clubs, you don't want to be interpreting 4c as Gerber all the time on all sequences. Bad club players want every 4c bid to be Gerber; good players use it on specific defined sequences only, and it just comes up extremely rarely, as usually some other sequence is better (to find suit slam with extra chances vs playing in NT, sometimes to find grand in a suit when 6 is the limit in NT).

[Gilithin]

euclidz, on 2023-April-28, 11:34, said:

Reading the responses to my post seems to confirm one of the points I put forward and that RKCB is only of any value when a suit is agreed . . . . apart from having no value in NT slam contract I would like to know (if anyone could point me to a piece of reading) what the RKCB bidders bid when there in no suit agreed; as the RKCB response bids all indicate K and Q key cards in an agrred suit what is bid when a suit has not been agreed?

RKCB is by definition only used when there is suit agreement and this is one of the more important aspects for club/social players to get sorted out when moving over to it. If we are looking for a NT slam, it is usual not to use any check for aces/kings at all. If we have the traditional 33hcp then we are not missing 2 aces; and if we have 37 for a grand then we are not missing any ace at all. The original use of Gerber (other than for Mr Gerber himself) was less about avoiding a NT slam missing 2 aces and more about having a convenient way of bidding very strong one-suiters. When Jacoby Transfers and advanced follow-ups to them became established, the number of hands where Gerber became a key factor diminished to the point that almost no strong pairs were using it regularly. There are of course many pairs that use 4♣ after suit agreement as RKCB (Baze) though. For hands without a long suit after a NT opening, either using Stayman, some version of Baron or bidding some number of NT is typically a good way of proceeding. There is no need to leap directly to asking about the number of aces.