MrAce, on 2011-January-22, 00:48, said:
U need to either give up on RKCB or controls.
Usual highjacking:
A modified version of culbertsons ace-checking-mechanism solves this.
Here 4NT is like a cuebid, except that it shows 3 aces and says nothing about controls.
Partner will now know that an ace, but only one, is required for cuebidding.
A direct cuebid would show excactly two aces, thus partner would require two aces to make a cuebid.
My own official add-on is, that 5
♠ would show 4 aces, but still only invite partner to bid slam. In other sequences 5
♠ has another meaning; like 1
♠-4
♣, 4
♥ - 5
♠. Here it shows only one ace (two is required for a 5-level cue), but otherwise an absolute maximum. Thus opener would not always be forced to pass 4
♠ on a dubious hand with 3 aces.
Pro's: So you can both check aces and controls. And in sequences where all controls are shown below 5 of the agreed suit, a chance to reinvite is given; 1
♠ - 4
♥, 5
♣ - 5
♦, 5
♠ = I'd rather bid slam than not, but you can have a say too. (Yes, I know 5
♥ could have that meaning too, but in non-splinter-sequences that is not an option.)
Con's: You need a lot more agreements, and accidents are bound to happen in the implementation-period.
General: This method shines the most in competitive sequences, and in systems where you volontarily use up a lot of space on not-so-well-defined bids.
Some say that playing this in the "denial-cuebid" way is even better. So after 1
♠-4
♥;
4NT: Denies three aces.
5
♣: Shows three aces and denies club-control.
5
♦: Shows three aces and club control, denies diamond-control.
5
♥: Shows three aces and club and diamond control, but denies heart control.
The same principles apply for the next bid; not going back to thrumphs shows control in the suits partner has denied control in, but denies it in the suit bid. I have never experimented with this, but at a glance it seems like you are insured to always be able to check controls surely, but you lose the occasional re-invite option. Also, it seems like you'd need even more agreements.