Bot causes the Hearthstone client to lock up when doing moves

I just watched the bot screw up a turn because it left a Shadow Word: Death until the last action in the turn, but it ran out of time before it could play it.

The bot wasted a majority of the turn time waiting for the client to unfreeze. It doesn't freeze after every action, but does after most.
Looking at the live output, it seems to correspond with the calculating stuff portion, but most actions only take 100ms or less, according to that output, yet the client will frequently freeze for a second or two, and this adds up significantly.

The freeze also makes it frustrating to watch the bot play.

Other bots that I've used don't have this issue. Is there a way for the bot to perform without locking up the entire client?