[echo25]

 kontoleon, on 2015-May-01, 16:42, said:

I am not expert but i personal i just risk the 4nt here if i am N with open hand by dummy, 3 key and singeton C is no big risk here the 4NT.

I cant imagine hand with 12 points that is no enought here from at least 5s...

AQxx
xxx
Qxx
KQJ
14 points, 5S-1 after heart lead.

[GrahamJson]

I suggest that 4C is only Gerber opposite a 1nt opening.

4nt is Blackwood if your or p's last bid was not nt.

[m1cha]

 manudude03, on 2015-April-30, 20:41, said:

Bid these 2 hands (south dealer):

---

Get to 6S? Good. Now bid them with south's hearts and clubs switched.

As is,
1♣ - 1♠ -
2♠ - 3♥ -
4♠ - 4NT -
5♦ - 5♥ -
[♠Q] - 6♠ -
- -

Reversed,
1♣ - 1♠ -
2♠ - 3♥ -
3♠ - 4♠ -
- -

Long-suit trial bids (3♥) are meant for evaluating the chances of a full game, but can just as well be used as a kind of low-level quantitative slam invite. With the reversed hand, S has a sure minimum hand and declines. With the first hand, S might accept with optimum ♥ support in spite of minimum count.

By the way I think we shouldn't worry if we don't reach slam here. The slam is cold, of course, but take ♥Q and give ♣Q, or take ♣7 and give ♦7, and it fails.

[m1cha]

 GrahamJson, on 2015-May-02, 02:58, said:

I suggest that 4C is only Gerber opposite a 1nt opening.

4nt is Blackwood if your or p's last bid was not nt.

It seems to be a kind of standard these days that 4NT is a quantitative invite if partner's last bid was NT (and Blackwood otherwise), and that 4♣ is Gerber only directly after a natural NT opening (1NT, 2NT) or it's equivalent (such as 2♣ - 2♦ - 2NT). The reason for using Gerber here is not to keep the bidding low - which is not necessary as explained by helene_t - but because 4NT is not available.

Consequently I sympathize with the position to play Gerber whenever 4NT is quantitative, that is, whenever partner's last bid was NT, though it appears to be non-standard and though I am not playing this myself when ♣ was bid naturally during the auction. Right, if I think of running from 3NT for some reason, 4♣ does not look like a winning contract in the long run. Rather pass, risk 5♣ or try to sign off in 3♣ earlier. But when ♣ was bid naturally and 6♣ is a possibility, I want to play 4♣ as a slam try for this suit (perhaps Optional Minorwood). I don't have a partner who would play Gerber with me in this situation. But as a working rule for the beginner level it seems good to me.

Gerber over suit contracts should not be taught any more, it will be mistaken for splinter, for a cue bid or else by most others players in modern bridge. Once you start feeling Blackwood is no help in minor suit contracts, learn Minorwood or perhaps Kickback.

By the way, some here mentioned that asking for aces is overrated, and I don't object. But I also suggest that some of these quantitative invites are also overrated if partner's point count is already restricted to a narrow range. When you have a good trick source such as a 6-card minor, you can make 13 tricks with a combined 31 HCP, so there are more important things to check than a single HCP above maximum in partner's hand. For example, just yesterday I had this bidding with a robot partner:

2♣ - 2NT -
3NT - 4NT -
6NT - - -

The thing is, 3NT was labeled as exactly 22 HCP and 4NT was labeled as 12 HCP and a quantitative slam invite. So I looked at my hand wondering if I have a 22-point minimum or a 22-point maximum, found my nice 5-card ♣ suit and bid 6NT, going down 1, where Gerber or Blackwood would have shown the two missing aces . Though I believe if one of my regular partners bid 4♣ here, I would understand it as Stayman, not Gerber, but this is a pretty exceptional case.

[zillahandp]

No forget gerber unless it goes 1/2nts, 4c or forget it entirely please

[m1cha]

 zillahandp, on 2015-May-02, 16:22, said:

No forget gerber unless it goes 1/2nts, 4c or forget it entirely please

I am aware your treatment is standard, so it must have a point, but unfortunately I don't understand this point. So could you or someone else please explain me what is wrong about 4♣ as Gerber in situations such as

1♥ - 1♠ -
2♥ - 3♦ -
3NT - 4♣

1♥ - 1♠ -
2♦ - 3NT -
4♣

1♥ - 1♠ -
2NT* - 4♣** -
* 18 - 19 HCP with 5-card ♥, no ♠ fit
** 3♣ would be natural and forcing to game

1♦ - 1♥ -
1♠ - 2♣* -
2NT** - 4♣***
* 4th suit forcing, at least invitational
** ♣ stop, (semi-)balanced, 2 or less ♥ cards
*** 3♣ would be natural and forcing to game (unless ... 1♥ ... 3♣ is)

if I think we're strong enough for a slam based on points or tricks but I want to check if 2 aces are missing. Of course I can bid 4NT quantitative if I prefer.

[manudude03]

In short, asking for aces doesn't tell you if you have 12 tricks, only that you aren't losing the first two. And by using 4C as gerber, you are giving up a very useful bid (to find how well the hands fit) for a relatively minor benefit. As for the 3 sequences you posted:

1. 4C looks like the bid with AKxxx xx AKxx Ax. The problem with having 4C as gerber here is what do you do if partner shows say no aces and 2 kings? Partner could easily have Qx Kxxxxx QJ KQJ or something where slam is hopeless* or xx KQJTxx Qx KJx where slam is almost cold.
*Actually 6S/NT has play, but you still wouldn't want to be in it.

2. 4C here is traditionally natural and tends to be a quantitative 4NT hand or better with 1543 shape. Maybe you can get to a 4-3 6C contract or 4-4 6D contract if partner chose to ignore the fit the round before.

3+4, If we had agreed gerber, I would play them in those auctions. I would say though, that in strong partnerships 3C in sequence 3 is becoming very rare, but that's for another topic.

[helene_t]

Mike Lawrence plays gerber in many situations and when 4c has to be something else he sometimes plays 4nt as quanti and 5c as gerber. Inquiry from this forum also likes gerber.

So while 4c in most situations is better used as natural, autosplinter, cog or control, it is not necessarily bad to play it as gerber in some situations. However, it becomes very complicated to determine when it applies so if you want to keep things simple it is better never to play gerber. This argument is relevant for everybody but especially for beginners, of course.

[Lovera]

Gerber is used on balanced hands (opening bid 1NT or 2NT ..4♣ either by partner or opener) and over 2♣-2x followed by 2NT whilest 4NT when you are agree trump suit in the other cases. So it allows you to use cue bid and identify easly that 4♣ is a cue (showing A of club). With the occasion i want suggest to find and see also the 4♣ by Walter Avarelli (that i used instead Gerber) that allow you (expecially for first answere indicating 0/1 Ace) to stay low in bidding.

[m1cha]

 manudude03, on 2015-May-04, 20:29, said:

1. 4C looks like the bid with AKxxx xx AKxx Ax. The problem with having 4C as gerber here is what do you do if partner shows say no aces and 2 kings? Partner could easily have Qx Kxxxxx QJ KQJ or something where slam is hopeless* or xx KQJTxx Qx KJx where slam is almost cold.
*Actually 6S/NT has play, but you still wouldn't want to be in it.

Partner has shown 12 - 15 points, I have 19 including a pretty fragile length point, no good fit. How do we evaluate the chances of a slam? Sure I may appreciate 4♣ for cue bidding, but will it solve my problem?
The main two differences between your two hands are the overlap in ♣ and the ♥Q. Will I find that out? Traditionally I can bid 4NT to ask partner about the precise range but is this likely to solve the problem? Bridge is a matter of probabilities. I prefer to ask for aces and raise to slam based on the presence of the ace. Why? Because if the ace is missing I'm sure to concede a ♥ trick and I think I'm more than 50 % likely to concede another trick anywhere else with our few points. But when the ace is with partner, the suit will almost certainly hold. It will hardly ever be lead and if it is, partner is likely to have a double stop, so I can afford to concede a trick in another suit. And if I think I'm more than 50 % likely to concede two tricks in other suits, I shouldn't think of slam at all. In addition, that approach prevents bidding slam if partner holds ♥QJTxxx.

 manudude03, on 2015-May-04, 20:29, said:

2. 4C here is traditionally natural and tends to be a quantitative 4NT hand or better with 1543 shape. Maybe you can get to a 4-3 6C contract or 4-4 6D contract if partner chose to ignore the fit the round before.

Yes, that's how GIB plays it iirc. And yes, playing IMPs I do prefer 6♣ 5-3 or 6♦ 4-4 to 6NT if I have that fit and a distributional hand. That's okay but I feel I don't necessarily have to bid 4♣ for that. How about playing natural over 4NT? So if partner is interested in slam and has an unbid suit, they bid 5♣ or 5♦ and we find the fit and slam in a minor.

@helene_t:
Right, the rules must be clear and preferably simple. Actually that's why I want to play Gerber. Otherwise I'd be fine playing 4NT to ask for aces even for a NT contract whenever it doesn't make sense to play quantitative 4NT. But unfortunately there's no general agreement possible about what "makes sense" and what doesn't . Whereas it is pretty simple to strictly define a set of situations for Gerber 4♣. While on the other hand again, there is obviously no agreement on the question if this set "makes sense" .

By the way, I never played 5♣ Gerber so far. But I used to play 4♦ as Gerber in a few selected situations (where 4♣ was defined differently).

[manudude03]

 m1cha, on 2015-May-06, 20:15, said:

Partner has shown 12 - 15 points, I have 19 including a pretty fragile length point, no good fit. How do we evaluate the chances of a slam? Sure I may appreciate 4♣ for cue bidding, but will it solve my problem?

The point is that by cuebidding, you may get partner to do the asking, and he will be in a much better position to place the contract.

 m1cha, on 2015-May-06, 20:15, said:

Yes, that's how GIB plays it iirc. And yes, playing IMPs I do prefer 6♣ 5-3 or 6♦ 4-4 to 6NT if I have that fit and a distributional hand. That's okay but I feel I don't necessarily have to bid 4♣ for that. How about playing natural over 4NT? So if partner is interested in slam and has an unbid suit, they bid 5♣ or 5♦ and we find the fit and slam in a minor.

The problem with looking for the minor suit fit after bidding a quantitative 4NT is that partner might reject the invite with a minor suit slam on.

[gszes]

 keithhus, on 2015-April-30, 05:58, said:

because of some recent experiences, I am thinking of advising my partners that 4 Clubs is always gerber and 4 NT is always Blackwood, regardless of previous bids. Bearing in mind the level I am playing at, do you think this is a sensible approach? Thanks

I did not read all of the advice (30 responses) but the first few missed an important point ---- it is not reasonable to have (when both are available) to have 2 ways of asking for aces. If you really feel the need to simplify it is probably best (when both bids are available) to use 4c as always gerber and 4n as quantitative. I do not recommend this arrangement because slam bidding involves some of the most creative 9cue bidding) and enriching sequences in bridge (did I mention mind boggling?).

It is fine to try and win but learning is much more important than taking short cuts but that is up to you.