Source: www.larryco.com 
This deal was reported to me by Fred Theurkauf. It was played in the 2015 San Diego Regional at IMPs. South held:
Q 10 8 5 3 A K 10 4 3 2 A 2 —
Should he open the 5- or 6-card suit? This 6-5 conundrum has been around forever. Ideally, you want to open in the 6-card suit and if the majors were reversed it would be easy. Here, though, if you open in hearts, you risk having to “reverse” when you next bid spades. I think this hand with AK-A and beautiful distribution is worth reversing. So, I would bid the suits in “normal order,” starting with the 6-card suit. If you open 1, LHO preempts with 3, your partner passes and RHO contributes 3. Following through on your plan (though a level higher than intended), you volunteer 3. Partner perks up and you eventually land in 6 and see:
Maybe partner should have bid 3 himself. It turns out you’ve missed quite an excellent grand slam. West leads the A and RHO follows, you ruff. At the table, both expert players (as I was told) laid down the A to throw a diamond and then ruffed a heart. Next came the A on which LHO showed out. They played a spade to the 10 (for the marked finesse) and ruffed another heart. Disaster! RHO overruffed. Declarer still had to ruff two more red cards in dummy, but had only one trump with which to do so. Let’s follow this careless line of play with all 52 cards in view:
Declarer ruffed the A lead and played the A (needless) to throw a diamond. He ruffed a heart, played the A (dummy’s second trump) and a spade (dummy’s third trump) to finesse his 10. He now tried to ruff another heart in dummy, but was doomed by the 5-2 heart break.
It is true that the bad major-suit splits were unlucky, but after all, there was a preempt. There were some ways to overcome the careless start, but a much safer line was available.
Ruff the club lead and play a low heart from hand at trick 2. Trump in dummy and test trumps with the A. Play a spade to the 10 and trump another low heart in dummy (with the penultimate trump). Come to hand with the A and trump a third low heart in dummy with the K. Declarer remains with:
Q85 AK10 2 –.
East has only the J and West has only 2 hearts remaining. Come to hand with a club ruff, draw the last trump and lose only a diamond at the end. Declarer’s big error was that it seemed he was playing as if in a grand slam. Trumping two low hearts early virtually guarantees 12 tricks.
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