I am not pretending to have worked out the odds, but my line is to win the
♦K and lead a low
♣ to the J.
If this wins, I am almost assured of a make: lead the
♥10, and I can afford 2
♠ losers and will not lose control if trump are 4-1.
If it loses, then my line depends on how the defence goes. If RHO leads a low
♠, that might be from Axx or from Qxx, and I need to guess. If RHO leads the A and a
♠, that is probably from Ax but might be from AQx.
Assume that I get the
♠ guess right half the time: now I have to guess again: does the short
♠ hand have 2 or 3 trump? If 2, then I must play A and a trump. If 3, then I have to hope the K is onside.
Bear in mind that I will by then have some clue: rho will have shown the
♦Q (because of the lead) and the
♣K. If he also has the
♠A, I will not play him for the
♥K.
I think my line is 50% (roughly) when the
♣ hook wins and about another 15% or so for when it loses (If the
♠ guess is relevant, I get it right 50% of the time and I then get the trump right most of the time when it is possible).
The problems with Hannie's other two lines include the giving up in trump (unless the K is stiff), which means betting that you can hold your black suit losers to 2: most of the time you can do this, my line works as well, and my line works half the time that you have to lose 3 black tricks.
The 3rd line: winning trick 1 n dummy seems to me an unnecessary risk: you create a tap suit for the opps and you are almost always failing when trump are 4-1 unless both the
♣K and
♠Q are onside.
But this is the type of hand on which the Rodwells and Rosenbergs of the world demonstrate their strengths: I bet they'd know the correct line, percentagewise, while I am sort of fumbling my way to the answer
'one of the great markers of the advance of human kindness is the howls you will hear from the Men of God' Johann Hari