Check my thread for this topic. You are exactly right there is a set clock in the CPU's QB head that if he feels he has all day to throw he will take the deep shot more often then not. But if he senses pressure he try and get rid of the ball sooner. Sometimes they might not see anyone open and they'll take a coverage sack which is why so many guy's are either getting too many sacks or why they aren't getting much pressure at all.
Those Two Sliders you just mentioned is a direct result of this and guy's are boosting up the QBA Slider and it really doesn't have to go up it's a very sensitive issue within the Blocking Sliders and BRK BLK Slider that triggers a reaction out of the QB's more often then not.