Just wondering about this, are you required to press the button prompted more than once for Prof mode? Because I'm sure I'm pressing the button within a second and the game just pretends I never pressed it at all. This is particularly noticed in Ndesu fight for example - In Veteran Mode it would instantly react to the QTE prompt, but on Prof Mode it seems to ignore me having pressed it about 85% of the time.
Are you pressing the right button first? Because in pro pressing the wrong one first will = automatic fail even if you press right one after in time. You need to press the right button first. Makes dodging in pro way more harder.