Click. If used correctly it will improve your target panic.
How so?
I 100% disagree.
30+ years of experience as a shooter, competitor and coach in a variety of disciplines have convinced me otherwise. The click is in there because of the snake oil being sold by Joel Turner. The Shot IQ stuff is nothing more than an overcomplication of a simple process, with some clever re-wording of some well-known concepts to try to make it sound new and flashy. He's done nothing more than create a problem and provided multi-step solutions to it. Look around and see who all he pushes this whole "click" stuff on. The only people buying it are new shooters, and shooters with poor form who continue to chase accuracy.
The original intent of a click was for a hinge release. Most often, one side of the half moon had a click, which could be turned around for no click, once you learned how to draw and shoot with back tension. The click served as a safety of sorts, and as a means to help the shooter learn repeatable hand placement. It has no place or purpose in a thumb button or index release. As you're executing your shot, you're now interrupted by a click once you're settled in to position. It will be a matter of time before that click causes the "oh shit, the release is about to go off", and target panic sets in. It's just the way shooting works when the process is interrupted.
Step 1: Develop good form habits that are repeatable.
Step 2: Aim with your form and eyes. Keep your mind out of it.
Step 3: Let the large muscle groups of your draw shoulder execute the shot, with ever so slight forward pressure of the bow arm. This prevents the perception of movement that triggers "panic" in the mind. Adding a click in there will 100% eventually bring someone with target panic full circle, if it even gets them out at all. The most widely used method for correcting target panic issues is blank bale with a hinge that is set cold, or a thumb button that is set heavy.
Don't take my word for it just yet ... go buy a Onnex click or Solex click and learn for yourself. Please. Really. Go do that and shoot under pressure in competition or hunting for a while, and report back how things went. Then, take a look down the line at any major archery event and see how many are shooting thumb or index click. Hell, Joel's own son isn't even shooting an thumb or index click in competition.