How proceed to 6C

[kenrexford]

Just noticed all of this, and I did think that West opened. Duh!

 

My approach:

 

1♣-P-2♣-P-

 

(2♣ is artificial GF or LIM raise)

 

2♦-P-2NT-P-

 

(2♦ showed hearts, 2NT shows balanced with club support and GF)

 

3♠-P-4♣-P-

 

(3♠ showed 4441 with interest, 4♣ was a cue of two of the top three clubs; note that RKCB for clubs is no longer necessary)

 

4NT-P-5♥-P-

 

(4NT was RKCB, but Responder is to show the K and Q of hearts rather than the K/Q of clubs; 5♥ showed two without the heart Queen)

 

At this point, Opener knows that Responder has the heart King, solidifying the hearts for four tricks. The clubs are equally solidified for four tricks. With the known diamond Ace opposite, we also take a minimum of the two Aces and a diamond ruff. However, that gives Responder a mere 12-count with only four clubs, which is hardly a 2NT rebid. We clearly have 12 tricks somewhere, therefore. With solid hearts and solid-enough clubs, both Aces, and 12 seen, a grand try is in order.

 

Whatever Opener elects, Responder is looking at the fifth club and the third diamond and therefore has no problem bidding the grand.

[gnasher]

1♣-P-2♣-P-

 

(2♣ is artificial GF or LIM raise)

 

2♦-P-2NT-P-

 

(2♦ showed hearts, 2NT shows balanced with club support and GF)

 

3♠

 

(3♠ showed 4441 with interest

You were doing really well up to here, but surely now it's better for responder to be in control? He knows that three key cards and either ♥Q or ♠K is good enough for a grand slam (opposite Axxx AQxx it needs hearts 3-3 or a major-suit squeeze). Opener, on the other hand, can never know where the 13th trick is coming from unless he can find out that responder has only five major-suit cards.