[Liversidge]

I have been learning about quantitative bidding for No Trump slams, 33 HCP for small slam, 37 for grand slam. When partner opens 2NT (20-22 HCP) and I have 11- 12 HCP, I bid 4NT and partner passes with a minimum and raises to 6NT with a maximum.
We use KCB for suit slams, and I have just received some advice on using Gerber to ask for aces before signing off in a No Trump contract. I am not sure how this is better than straight quantitative bidding, which is a lot simpler. With 33 HCP the partnership could be missing AK, AQJ, KKJ, KQQ, QQQJ, and I can't see how Gerber adds any additional safety. (I can see why neither RKB or Gerber are not good when there is a known void or weak doubleton, so cue bidding is used) Could someone give me an example of a situation where Gerber adds value.

[Cyberyeti]

Where gerber adds value opposite 2N ? :

KQx
x
x
KQxxxxxx

All you need to know is how many aces, Blackwood may be too high if the answer is 2. Gerber is not the answer for pure NT slams, one of the ways of responding to 2N-4N is to show aces if accepting.

[Zelandakh]

Gerber was traditional used for strong distributional hands. Typically a hand with a long suit that could place the contract upon finding out how many aces partner owns. This is to some extent redundant in modern 1NT structures because it is usually better to set the suit first. For balanced hands I do not recommend using Gerber at all, ever. Instead just use your quantitative raises.

Edit: CY beat me to it with an example matching my description. Suffice it to say that there is a modern way (actually more than one) of dealing with this hand without using Gerber. It is just the methods I am thnking of are not really suitable for this forum.

[Liversidge]

Suppose partner opens 2NT with 20 HCP and I hold (clubs first)
xx
AKJxxxx
x
Kxx

Quantitative bidding won't get to 6NT. Gerber might. Or is there another way?

[Cyberyeti]

Liversidge, on 2014-March-04, 14:13, said:

Suppose partner opens 2NT with 20 HCP and I hold (clubs first)
xx
AKJxxxx
x
Kxx

Quantitative bidding won't get to 6NT. Gerber might. Or is there another way?

Firstly, the standard is to display spades first, try using the hand editor (the spade symbol at the far right of the line of icons)

---

for example.

This is now a methods thing. Say you use 4♦ as something conventional over 2N (either transfer as many people do or both majors as we do), you need a way of showing a hand with a diamond suit so you use it, for us this is 2N-3♠-3N(forced)-4♦, now partner should cue. Depends on cue bidding style (first round first or first/second) what happens next but playing my preferred style (cue anything) it likely proceeds 4♥-4♠-4N and you're on a guess whether you show Q♦ or not, I probably would as it will enable partner to know you have the 7th diamond if he has the Q, or judge correctly with xxx if he hasn't, it may lead you to a grand opposite xx however.

[Zelandakh]

Liversidge, on 2014-March-04, 14:13, said:

Quantitative bidding won't get to 6NT. Gerber might. Or is there another way?

I do not use Gerber over 2NT and this hand gives me a chance to tell you what I play instead, namely that 2NT - 4♣ shows diamonds in the same way as Texas transfers of 4♦/4♥ show hearts and spades respectively. Then 4♥ over 4♦ is RKCB. This loses 2 steps to the immediate Gerber but in return the trump suit has been set. It would be unusual for Gerber to work here and this approach not to. The advantages of this over CY's approach are right-siding diamonds, an extra step and that 2NT - 3♠ now guarantees clubs; the downside is that he can use 4♣ for something else and an artificial 3NT response fits better. Iirc he also passes his 5-4 minor hands through 3♠, which would also limit the usefulness of 3♠ showing clubs (my 5-4s usually go through 3♣ instead).

As usual, the important thing is having a joined up system. Hopefully the above does at least show you how little use Gerber is in a good response structure. You just gain much more flexibility by setting the suit and asking. As an example of this last point, change the ♦K to the queen in your test hand. Now Gerber is useless but setting diamonds first still gets the job done. The discussion that we could have between RKCB and a cue auction after having set diamonds is much less important than the more fundamental one of whether we set diamonds in the first place. And it is the development of methods such as these that has led (mostly) to the demise of Gerber.

[MrAce]

Zelandakh, on 2014-March-05, 04:55, said:

I do not use Gerber over 2NT and this hand gives me a chance to tell you what I play instead, namely that 2NT - 4♣ shows diamonds in the same way as Texas transfers of 4♦/4♥ show hearts and spades respectively. Then 4♥ over 4♦ is RKCB. This loses 2 steps to the immediate Gerber but in return the trump suit has been set. It would be unusual for Gerber to work here and this approach not to. The advantages of this over CY's approach are right-siding diamonds, an extra step and that 2NT - 3♠ now guarantees clubs; the downside is that he can use 4♣ for something else and an artificial 3NT response fits better. Iirc he also passes his 5-4 minor hands through 3♠, which would also limit the usefulness of 3♠ showing clubs (my 5-4s usually go through 3♣ instead).

As usual, the important thing is having a joined up system. Hopefully the above does at least show you how little use Gerber is in a good response structure. You just gain much more flexibility by setting the suit and asking. As an example of this last point, change the ♦K to the queen in your test hand. Now Gerber is useless but setting diamonds first still gets the job done. The discussion that we could have between RKCB and a cue auction after having set diamonds is much less important than the more fundamental one of whether we set diamonds in the first place. And it is the development of methods such as these that has led (mostly) to the demise of Gerber.

Never heard before but I kinda like it.

[Cyberyeti]

Zelandakh, on 2014-March-05, 04:55, said:

I do not use Gerber over 2NT and this hand gives me a chance to tell you what I play instead, namely that 2NT - 4♣ shows diamonds in the same way as Texas transfers of 4♦/4♥ show hearts and spades respectively. Then 4♥ over 4♦ is RKCB. This loses 2 steps to the immediate Gerber but in return the trump suit has been set. It would be unusual for Gerber to work here and this approach not to. The advantages of this over CY's approach are right-siding diamonds, an extra step and that 2NT - 3♠ now guarantees clubs; the downside is that he can use 4♣ for something else and an artificial 3NT response fits better. Iirc he also passes his 5-4 minor hands through 3♠, which would also limit the usefulness of 3♠ showing clubs (my 5-4s usually go through 3♣ instead).

As usual, the important thing is having a joined up system. Hopefully the above does at least show you how little use Gerber is in a good response structure. You just gain much more flexibility by setting the suit and asking. As an example of this last point, change the ♦K to the queen in your test hand. Now Gerber is useless but setting diamonds first still gets the job done. The discussion that we could have between RKCB and a cue auction after having set diamonds is much less important than the more fundamental one of whether we set diamonds in the first place. And it is the development of methods such as these that has led (mostly) to the demise of Gerber.

Full discussion of methods here is probably beyond the scope of the N/B forum, but suffice it to say nothing is perfect and it's just a case of agreeing what you do, 2N is not known as the slam killer for no reason. Last time I used gerber over 2N, IIRC I had something like x, KQxxxxxx, Kx, Kx and that was several years ago, so there's an argument for using 4♣ as something else. Zel is right about what I play, we put all hands with slam tries with one or both minors through 3♠, although we don't play an artificial 2N-3N purely because it's such an easy one to forget, even though it would be more efficient.

[Zelandakh]

MrAce, on 2014-March-05, 05:26, said:

Never heard before but I kinda like it.

Bah, I posted it enough times already! Last one I can find is here if you want to see more. That is a fair while back but I do not think I changed too much since then.

[ArtK78]

Liversidge, on 2014-March-04, 14:13, said:

Suppose partner opens 2NT with 20 HCP and I hold (clubs first)
xx
AKJxxxx
x
Kxx

Quantitative bidding won't get to 6NT. Gerber might. Or is there another way?

In the absence of special methods, hands like this one become a matter of judgment.

One point that has not been explicitly raised is that Gerber, like Blackwood, is an ace asking convention. Its purpose is to determine whether two aces are missing. It is not a slam try; rather, it is a safeguard to avoid slams with two quick losers.

On this hand, one might decide that, opposite a 2NT opening bid, you want to be in slam if you are not missing 2 aces. I don't believe that is all that there is to this hand, but it is a position that one might take. In that case, you can bid Gerber and, if the partnership is not missing two aces, bid 6NT (or 6 of your long suit, which I believe is diamonds). There are obvious problems with this approach, but the hand may be difficult to bid using any methods once the auction starts with 2NT (the 2NT opening bid is sometimes referred to as the "slam killer" because it is often difficult to bid to making slams with any confidence after the 2NT opening).

Note that pure point count bidding accomplishes the same thing in a different manner. If the partnership has a combined 33 high card points, the partnership cannot be missing 2 aces (It can be missing a cashing AK, but that is another matter). If the partnership has a combined 37 high card points, the partnership must have all of the aces. There is no guarantee that 33 high card points will result in 6NT making, just as there is no guarantee that 37 high card points will result in 7NT making. But experience has shown that these are reasonable guidelines for bidding with a balanced hand facing a balanced hand.