Fit Jumps Opener has 5422 Hand 9

Board 9 North Deals	♠ K J 6 3 ♥ A 8 ♦ A Q J 10 8 ♣ 6 4
♠ 8 ♥ K 10 9 7 6 5 4 3 2 ♦ 7 ♣ 9 3	N W E S	♠ 10 7 5 ♥ Q J ♦ 6 4 ♣ K J 8 7 5 2
	♠ A Q 9 4 2 ♥ — ♦ K 9 5 3 2 ♣ A Q 10

West	North	East	South
	1 ♦	Pass	2 ♠
4 ♥1	4 ♠	Pass	5 ♣
Pass	5 ♦	Pass	5 ♥
Pass	6 ♥	Dbl2	6 ♠
All pass

Preempt -- twice rebiddable ♥; 3-25 total points 2+ ♥; 7-16 total points

6 ♠ by South

Lead: ♥ 10

Made 7 — NS +1010

Things are slightly different when fourth hand competes. North is under pressure to show support so 4 ♠ is quite a wide range. Here south has extra distribution and strength. In a competitive auction after we have established a fit (double fit here) our bids have a different priority. In particular we need to be able to show whether or not we have a control in the opponent's suit.

Therefore a raise to 5 ♠ would be invitational but without a control in the opponent's hearts and a cue-bid of 5 ♥ would be invitational with a control in hearts. RKCB is still on. Other cues are still more serious slam interest than 5 ♠ or 5 ♥ and looking for a missing control.

The auction here is routine up to 5 ♥. At that point north knows that south has a very serious slam hand with either a missing control or interest in a grand. North's 5 ♥ therefore shows extra values and a heart cue.

As an alternative north could take control with 5 NT which we would play as RKCB - one step above our trump suit at the five-level is kickback. South would show two and north would have to guess whether south has the ♠ Q, ♦ K and ♣ K or equivalent extra. At that point south will be known to have ♠ A, ♣ A and enough to make a serious slam try. The ♠ Q and ♦ K only take us up to thirteen hcp, so south will have something extra.

Some of these fine deductions are easier when you have a regular partnership and you know how optimistic or pessimistic partner is likely to be. I think it is close to bid the grand on the available information.

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