An Anomaly

10 6 5 3
9 4
A J 10 9 8 7 3
------
Q J 8 4 7
6 5 3 Q 10 7 2
K 2 6 5 4
8 7 3 2 K J 10 5 4
A K 9 2
A K J 8
Q Contract: 6 spades, 6 diamonds, 6 no
A Q 9 6 Opening lead: 8 of clubs

Whoa! This "violates" two of the foremost principles of bidding: the major over the minor and the balanced over the unbalanced suit for trump! It is clear that the unbalanced diamond suit will allow slam while the balanced spade suit will not! However, before any readers decide to throw in the towel on the two aforementioned principles, I would like to point out a few undeniable facts, namely that there is bad luck in the spade suit, and extraordinay luck in the diamond to allow that holding to bring home the suit without loss.
The spade suit not only has an against-the-odds 4-1 split, but had that singleton been one of the honors, it looks to me as though declarer could have pulled the slam off, with all side suits clearly stopped. As for diamonds, well, what more can you ask for? A once-guarded king! The only holding aside from a stiff that would allow you to pick up the suit! That's too much to hope for, though you can't resent those fortunate enough to have landed in diamonds. I guess they deserve it. (I'm reminded of the fellow who complained that he'd followed an 87% chance and lost to that little ol' lady over there who blithely followed a poor percentage play -- suggesting that his 87% chances should work in his favor 100% of the time.)
Before leaving the hand, I'd like to suggest that spades would probably better serve N-S here more often than the diamonds. In fact, take out a deck of cards, select out the N-S cards and shuffle the E-W cards about 5 times dealing them out. Now for a buck a point, I'll take six spades and you take six diamonds, okay? Well, of course, we're not going to wager on this, but the interested reader might trying dealing out the E-W cards that often and seeing how the results stack up. I certainly wouldn't be ashamed to be in spades. Unhappy, maybe, but not ashamed.
This hand is given in spirit of reminding the reader that none of these principles work out right a 100% of the time and is certainly not meant to inculcate a cyncism about the principles. But ultimately you decide for yourself. Keep your eyes peeled. And in the meantime, look at the next hand that surfaced within a few days of this one.

Oh. I almost forgot. Six no trump? Yeah, at least one declarer made it. But you can't make it without an improper cover. Without the cover, this declarer would have been down so far, he'd still be looking for a new partner. Don't cover an honor when you can SEE it can't help you! See Reasons for Not Covering. There's another principle I've pointed out several times, which is that when you cover, you do it to promote a lower honor (or spot card). So if you cover a queen with the A J 10 9 8 7 showing, you're covering to promote . . the six? I looked at the hand a second time to ascertain that the long diamonds were in dummy, for if the queen were in dummy, at least there'd have been some ambiguity to cover vs. non-cover. But they were in dummy all right. So I looked up the coverer's self-ranking and found that she's an expert. No comment.