[steve2005]

My link
This was a BEN just declare tournament
robot played queen under my King ♥ setting up 9
could have played 8

was just declare

this one is similar happened in same tournament

plays queen underneath K clubs

setting up 2 free tricks
My link second hand

[smerriman]

On the second hand (well always, but in particular), GIB is incapable of taking into account why declarer took a certain line. It sees the best chance as beating the contract as its partner having the jack of clubs, so it needs to unblock in order to get partner in. In fact the older version of GIB sees that as far better than low. Of course, declarer would never have played on clubs if that were the case.

Likewise, in the first case, unblocking does gain if partner has the 9 of hearts ignoring declarer's play.. though even with the old GIB not enough times for it to play it. The usual 0% bug is in play here too..

[steve2005]

smerriman, on 2025-January-10, 15:03, said:

On the second hand (well always, but in particular), GIB is incapable of taking into account why declarer took a certain line. It sees the best chance as beating the contract as its partner having the jack of clubs, so it needs to unblock in order to get partner in. In fact the older version of GIB sees that as far better than low. Of course, declarer would never have played on clubs if that were the case.

It wasn't Gib it was BEN

If robot likes to unblock so much, why didn't robot unblock Q♥ on second lead of hearts?
Then can run a bunch of hearts and lead a spade through declarer

[smerriman]

Oops, sorry, I missed that, though I expect the same applies.

[lorserker]

Playing the Q under the K is not a 0% play.

I don't argue that it's the best play, but it is correct in certain situations.
On the actual hand for example, if East has H9 and South has SQ then it's correct to unblock HQ.
If you say that the above is not realistic because declarer would have played differently, this is beyond what the robot is capable to infer.