Interrobng, on 2014-June-14, 17:16, said:
I am a beginner, and in my life I think I might have used cue bids once. My impression was that cue bids generally show control. So, if I open 1S, partner responds 2S, and I realize slam is a possibility, on the given hand I might have bid 3D (had I remembered that cue bids exist). That would have said two things: I can't control clubs, and I can control diamonds.
I have never before heard of using a cue bid to ask if partner can help with a suit, as earlier responders have recommended.
When does a cue bid show weakness in a suit, and when does it show strength in a suit?
Thanks very much!
RobR
To make a slam in a suit requires three things: Good trumps, good controls, and enough tricks.
Good trumps are important because, for example, if you get to slam on a suit like Axxx opposite xxxx, then you will definitely go down, or with Axxxx opposite xxxx you will often go down no matter what you have in the rest of the hand.
Controls are important because you don't want the opponents to cash two Aces, or the Ace King of a suit.
But even if you have great trumps and lots of controls, you still need to find 12 tricks! eg ♠AKxx ♥Axx ♦Kxx ♣Kxx opposite ♠QJxx ♥Kxx ♦Axx ♣Axx has great trumps and loads of controls and still only makes 10 tricks most of the time.
When partner has supported your suit with some sort of limit bid (eg 1♠ 3♠, or 1♥ 1♠ 2♦ 3♥) you generally have a reasonable idea of whether 12 tricks is a plausible target. So slam bidding becomes a matter of determining whether you have good enough trumps, and sufficient controls. This is why one of the most common approaches to slam bidding involves the partners cooperatively cue-bidding suits with controls to ensure there is no suit uncontrolled; allied with some sort of Blackwood to determine if the trumps and good enough, and there aren't 2 Aces missing.
Game in a suit, on the other hand, does not require so much. You don't need great trumps; you don't need every suit controlled; in fact, if it looks like you have the playing strength for ten tricks, then you are best off just bidding game and hoping you can set up and make your ten tricks before the opposition can make four. However, a lot of the time, whether the two hands have the combined playing strength for ten tricks depends on how well they fit together. A common way of finding out is bidding a suit in which you need help, and allowing partner to make the decision. This is generally known as a 'trial bid'.
If you are the responder, how can you tell whether partner is showing a control or asking for help? If you are in a game forcing situation, then partner's bid must be looking for a slam, and so is a control. If you are already at the 3 level, then partner's bid effectively forces you to game, so again it is a control bid. However, if there is still room for the partnership to subside in 3 of the major, then responder should initially assume it is a trial bid asking for help with a view to seeing if the hands fit well enough for game. I say 'initially assume', because if opener is slam interested he can start with a trial bid and then bid on even if partner tries to sign off at the 3 level.