my question comes about after the 4c bid... imagine opener has one of the top 3 honors and hears a 4c response.. now he *knows* responder has 5 cards with the A or K else 4 cards with A,K or K,Q or A,Q... can a cuebid now be either showing OR denying a control, based on the honor opener has, legally?
i know i'm not explaining this very well.. say you open 1h with K or Q 5th and pard bids 4c... you know he has A,Q or K,Q or just A, based on your own holding... further suppose you bid 4d now, and alert it as "diamond control if i have the A of trumps, no diamond control if i have the K or Q"
it's true that partner knows whether or not you hold a diamond control, but does this constitute u.i.? it seems to me that i don't *have* to tell the opps which honor i have, and the fact that partner knows doesn't seem to matter... but i could be wrong
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heck, the possibilities seem endless... ben, for example, plays 2nt over 1M as limit plus... if he just added the caveat that it means limit+ with either of the top 2, can't denial cuebids be used here also?
i think i have a headache