[quiddity]

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Matchpoints against robots.

LHO leads ♥Q to RHO's ace and you ruff the heart return. From the carding it looks like hearts are 4=6.
You draw three rounds of trump ending in dummy. RHO pitches ♦Q on the second round and a heart on the third round; LHO pitches ♣5 on the third round. Carding is usually standard count.
Who has the jack of clubs?

[MrAce]

 quiddity, on 2015-February-06, 16:51, said:

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Matchpoints against robots.

LHO leads ♥Q to RHO's ace and you ruff the heart return. From the carding it looks like hearts are 4=6.
You draw three rounds of trump ending in dummy. RHO pitches ♦Q on the second round and a heart on the third round; LHO pitches ♣5 on the third round. Carding is usually standard count.
Who has the jack of clubs?

LHO has QJ ♥, RHO for his opening has ♥A and ♣A, for his first discard he seems to have QJTx ♦, 1642 is a very likely shape E may be holding. Play a ♣ from dummy and see whether he has Ax or AJ doubleton ♣ for the overtrick?

[gszes]

These are robots sigh and they know where everything is so they make life (along with some really
sneaky humans) really tough when they can. A human (not knowing you have the dia K) would be hard
pressed to toss the dia Q w/o QJTx for the computer its an everyday thing since they know you have
K and our only decision is the club J so they try to mess with your head and mislead you. I would
play rho for AJx of clubs since its a robot. A human I would play lho for the club J

[Bbradley62]

 gszes, on 2015-February-06, 18:08, said:

... A human (not knowing you have the dia K) would be hard pressed to toss the dia Q w/o QJTx for the computer its an everyday thing since they know you have K and our only decision is the club J so they try to mess with your head and mislead you.

Everyone can see ♦K -- it's in the dummy (North).

[quiddity]

I played as Timo suggested, giving it very little thought. Unfortunately the hand was:

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Afterwards I thought it should be possible to work out the position. The robots use double-dummy simulations and they both have a bunch of safe heart discards, so their diamond/club discards must be from holdings where they can't cost (or else they are necessary for some corner case to avoid an endplay or whatever). With that in mind I don't understand the DQ discard; seems like it could cost if I have the T9 of diamonds and I don't see how it can ever be necessary.

When the robot declared the hand it played RHO for the jack as soon as it saw the club discard from LHO, so maybe the DQ is a red herring.