Fit Jumps Opener has 5422 Hand 16

Board 16 North Deals	♠ 8 7 ♥ A K 6 5 ♦ A 10 8 7 3 ♣ A 6
♠ J 6 5 3 ♥ J 8 2 ♦ 4 2 ♣ K Q 8 4	N W E S	♠ K Q 9 4 2 ♥ 10 9 ♦ 9 5 ♣ 10 9 7 2
	♠ A 10 ♥ Q 7 4 3 ♦ K Q J 6 ♣ J 5 3

West	North	East	South
	1 ♦	Pass	2 ♥
Pass	3 ♥	Pass	3 ♠
Pass	4 ♣	Pass	4 ♦
Pass	4 ♥	Pass	4 NT
Pass	5 ♣	Pass	6 ♥
All pass

6 ♥ by South

Lead: ♣ K

Made 6 — NS +980

Notice the comparison between this north hand and the last one. With aces and an ace-king this hand screens out for a suit contract.

After the fit-jump is raised south with prime cards but a minimum makes the mild slam try. North accepts and denies a spade control and shows a club control with 4 ♣. South reflects for some mental simulation (and stimulation). Giving north perfect cards we imagine ♠ xx ♥ AKxx ♦ Axxxx ♣ Ax. There are a few imperfections possible for example should north have the ♠ Q. Again however hands with ♠ Qx and a club control are going to be candidates for a 1 NT opening. So we can be fairly confident f the simulated hand. The only real variation is that south could have ♣ K and at least one jack.

South could probably justify 4 NT here counting five hearts (with a ruff), five diamonds, the ♠ A and the ♣ K (at worst on a finesse). However with the shown return cue of 4 ♦ it is now north's job to simulate.

Let's start by giving south perfect cards - ♠ Axx ♥ Qxxx ♦ KQxx ♣ xx. South has shown more than this but slam is cold opposite this much. If we remove two of these cards, say change the ♠ A to the ♠ K and remove the ♥ Q. And we would have to add five points in clubs (or spades but not the ace) - ♠ Kxx ♥ Jxxx ♦ KQxx ♣ Ax would be a mild slam try and slam would be poor.

North could bid 5 ♥ rather than the 4 ♥ shown. Then south with a nice minimum would go on to the excellent slam.

Otherwise in the auction shown south still moves based on the mental simulations described earlier.