If it's 50/50, as in "it was real close either way", you challenge each and every time. The math on this has been hammered out repeatedly, including in this thread.
If you want to talk about not letting emotions influence better judgment, then that means not being scared of the bad optics of a "mistake of proaction", and if it's a mathematically sound decision you do it, no matter how angry some fans might get. Why do you think coaches have for decades been far too timid in pulling their goalie, and it took a zero-****s-given man like Patrick Roy to open people's eyes? Why are football coaches petrified to gamble on a 3rd / 4th down conversion in CFL / NFL games? They're letting their emotions (in this case, fear) influence their better judgment.
Like, we definitely agree that it's bad when coaches do that, so that's good.