When traders feel emotion which results in physical symptoms such as change in heart rate it's because they haven't defined the finite set of possible outcomes for the setups they're trading. They are not only uncertain what's happening ...they don't have formal rules for how they're going to react to whatever price chooses to do next. Psychology? ...so much wasted time.
That is a very rational way of looking at it, but human emotion by nature is not rational. You can predict all the possible outcomes and still be anxious.

With your vast knowledge of B-Movies you must either be an ex-worker of some type from Hollywood or a former video store owner...just a guess. I can watch a film by Cannon Films anytime and it never gets old lol...