[Hanoi5]

Say the bidding goes:

1♣-1NT
3♣-

Would 3♥ show or ask for a stopper? Does it deny diamonds or spades?

What about:

1♣-3♣
3♦

And:

1♣-1♦
2♦-2♥

Do these bids show or ask for a stopper? What's standard? What's the best? What's the reasoning/rule?

[Quantumcat]

I'm not sure what's standard, but I have the agreement that bids show values when there's three unbid suits, or two if the opponensts have not bid or have only bid one suit; and bids are asking when the opponents have bid two suits (and we have the other two). Not sure I understand all the benefits but my partner has told me that's what we do :-)

So the first auction, 3♥ shows values. In the second, 3♥ shows heart values, denies spade values (otherwise you'd bid 3NT). In the third, 2♥ might just be showing values in hearts, or possibly a second suit if responder is strong and is hoping to find a 4-4 fit instead of a 5-3 one.

We also have the agreement, if the auction starts getting slammy, that bids at the 3-level or lower like the above just show values rather than a cue-bid (and actual cue-bids start at the 4-level). I have found this agreement really useful - for instance you have a side-suit AQ62 and will have 13 tricks if pard has KJ. You can't use 5NT because you have a singleton and the king in that suit would not help. However earlier in the auction he skipped this suit to show values in a higher one. So you know he does not have the KJ and can settle nicely in 6.

[P_Marlowe]

We play it as value showing.

Value asking may make sense, if the value / stopper ask was done by the
stronger side, the only possible auction would be #3.

If you play it as value showing it fits also fairly well with cue bidding,
so from a point of making things simpler / working well together, assuming
you value those things higher than any possible theoretical advantage -
value showing may be best.

You could also play it as shortage showing, ... alligning this with your
trial bids after a major suit fit got discovered.

With kind regards
Marlowe

[Zelandakh]

Standard is showing. There is a very small theoretical advantage to asking since this allows you to ask when you have no stop in any side suit. It is also simpler, since every suit asks whereas showing sometimes leads to situations where the last call (3♠) is best off asking. There is an unfortunate downside to this method playing standard when these bids could also be advance cues - you can switch to denial cues to compensate but now you are starting to change quite a lot. Another option for 1♣ - 3♣; 3♦ is as a general slam try in clubs (Frivolous if you like). If you do this then 4♣ becomes your serious diamond cue. That method works better in auctions where minor suit agreement at the 3 level is game-forcing or better though.

Anyway, the rule is simple. If we have minor suit agreement at the 3 level and 3NT is still in the picture as the ideal spot (ie we are not definitely slamming) then new suits are 2-way, either NT probes or cues. One assumes the former and partner will make it clear next round if it was a slam try. Which way round you play your probes/cues is a matter of agreement. Standard is to show values/controls. I personally prefer asking/denying.

[nigel_k]

Second or third suit is showing. Fourth suit is asking. No particular reason for this, but it does help to minimize accidents when partner interprets the bid as showing a real suit.

[Quantumcat]

nigel_k, on 2012-August-06, 18:54, said:

Second or third suit is showing. Fourth suit is asking. No particular reason for this, but it does help to minimize accidents when partner interprets the bid as showing a real suit.

The reason is probably if you had the last stopper you could bid NT, or something at the 4-level if you had slam in mind.

[Zelandakh]

The rule is the fourth suit but this can be an implied fourth suit too. For example,
1♣ - 3♣
3♥ - 3♠

The 3♥ bid shows heart values but denies diamond values. Therefore 3♠ has to show diamond values for interest in 3NT; but with values in both pointed suits we would bid 3NT. Therefore 3♠ shows diamond values and denies spade values. This is what I mean about the show method being more complicated in practise.

[oberiko]

Since I primarily play casually at work, we tend to keep it pretty simple and prefer that new suits are (almost) always value-showing. To clarify for the examples below, we play Acol w/ 4-card majors, weak-NT and inverted minors.

Example 1:
1♣ - 2♣ - 2♥ - 3NT

Shows:

• I have 4+ ♣'s, 12+ HCP and not a weak-1NT head
  
• I have 4+ ♣'s, 3- in both majors and 10-15 HCP
  
• I am denying a ♦-stop, but have a ♥-stop and would like to try for NT
  
• I have stoppers in ♦ and ♠ as well as 13-15 HCP

Example 2:
1♥ - 2♥ - 3♣ - 3♦ - 3♥

Shows:

• I have 4+ ♥'s, 12+ HCP and not a weak-1NT head
  
• I have 4+ ♥'s and 9 or 10 losers
  
• I have 6 losers and good ♣'s (at most 1 loser in that suit), if this is where 3 of your losers are, please bid game
  
• My losers are not in ♣'s, but I counter-propose with a strong ♦ suit (at most 1 loser)
  
• Signing-off in 3♥ as game isn't happening

For that reason, we also use the Eastern cue-bid instead of the (much more popular) Western cue-bid.