johnu, on 2017-January-06, 12:08, said:
Which doesn't work if East has ♣K(xx) and < 4 hearts, but does work if East doesn't have ♣K (or has < 3 clubs).
In that case, the squeeze may not operate but the hand can still be made - and with a much better count on it.
On the other hand, if I lead a club to the Q and it loses, I can now only use the squeeze if one player holds only 2 clubs.
I'm not sure which is the right play. I only know what I would do at the table - and a squeeze is always more fun that leading low to the Queen.
As to why I come to this conclusion, it is pretty simply. RHO should have 7 spades for his preempt over 2C. That leaves 6 unknown cards. LHO has 2 spades. That leaves 11 unknown cards. A priori heart split is 4-2, so LHO is more apt to hold the 4 as there is more room in that hand. That now gives LHO 4 hearts and 2 spades with RHO holding 7 spades and 2 hearts. The likelihood that LHO holds any one card - the club K - is 7-4.
So it seems to me the most likely holdings favors a line to play as there is a squeeze against LHO.