Diamonds aren't Mentioned?

9 7
K J 10 9 5 2
8
7 6 4 2
A K 6 5 4 2 10 8
------ A 4 3
K J 10 5 A Q 4 3 2
K Q 3 J 9 8
Q J 4
Q 8 7 6
9 7 6
A 10 5 Vul: None

WestNorthEastSouth
1 2 Pass 3
Dbl All pass

Down two. Whoop-dee-doo! Plus 300 when they have slam? (This hand was discussed with East here as declarer in 6 diamonds here. ) Actually, that pair did worse than this one, since it was misplayed for down one. Still and all, you don't want to look in on a post-mortem and find not that you were a trifle to aggressive nor too tame, exactly, but that you didn't even mention your 9-card suit!
I think East has to be the goat here. She was given two chances to name diamonds. With 11 hcp's and not vul, I would think an immediate bid of 3 diamonds would be warranted. Now that's opposite an opening bid! Eleven hcp's, including 2 aces is an awful lot to keep hidden. Actually, if you add a point for the doubleton spades, you've practically got that great desideratum of an opening bid opposite an opening bid, which everyone knows means you drive for game. But then West doubled and surely that has to be a re-opening takeout double. With not just a biddable suit, but a healthy biddable suit, a 4 diamond bid is surely mandatory there.
There is nothing like a fit. This one could actually have been entered under slam-dunk fits. For you'll notice that N-S have a superfit of their own, one card better in fact with 10 trump. They're missing a lotta high cards and can make only 7 tricks, but what of that? The superfit makes them impervious to disaster all the way to the five level, balanced against the slam potential. Now if with only 13 hcp's between them, they can find their best fit, don't you think that with 27 hcp's you'd want to be able to do the same?