Delicate Slams

Bidding slams is difficult. Holding 36 combined points a ten card major fit and one hand opens 2NT we all drag ourselves over the line. But when there's not enough points and the slam works on distribution it's tricky. Harder still is when you don't have the points or the distribution yet somehow slam can be claimed on the lead.

Give yourself these cards:

♠	A x x
♥	K x
♦	A K T x x
♣	Q J x

Good hand, no doubt.

But what if partner only has a 13 count? Chances of the 6 level slide a bit. There are still great chances if partner has a good fit right?

You've got an 8 card diamond fit and none other. As I've come to appreciate recently 9 card fits make slams more often that 8 card fits so this is discouraging. If partner had a partial fit for clubs or hearts and a spade shortage we still might try for 12 tricks wouldn't we?

Partner is 3433. Not even a 7 card fit on the side. Just give up here, 3NT is plenty.

Yet when the dummy comes down:

♠ A x x ♥ K x ♦ A K T x x ♣ Q J x		♠ x x x ♥ A Q J x ♦ Q J x ♣ K x x

6♦ is lay down. It'll survive 5-0 trumps on a non spade lead or 4-1 otherwise. All the tricks I use for evaluation fail to predict even the suggestion of slam.

• 30 points. Balanced hands usually work on HCP.
• 14 combined losers  (15 say some definitions) suggests 4♦.
• 59 Zar points (normally 62 required for slam).

Is this a curiosity of the game or is there a secret I don't know?