This broken record we hear every high school season drives me crazy! Why is it that these coaches feel the need to march up to pitchers who already have pitching coaches and procede to instruct pitchers on how to pitch?! Ignorance on parade!
Certifications are an interesting concept. I would argue that "certification" doesn't necessarily translate into what you might think it does. Sure, you'll find SOME "certified" instructors who are good. But you will also find some "certified" instructors who are not so good. Further, just...
"The whole point in I/R and brush is to whip... the change should not have whip."
James, I'm going to argue that you may have that whip with a knuckle-change, and it's even desirable with that pitch. While many experts abhor the knuckle-change, a main advantage is that you can throw it full...
For me (my observations), detachment at roughly 3:00, if not an absolute to strive for, is pretty darned close to an absolute. Given the vast majority of young pitchers underutilize leg-thrust in their leg-drive (i.e., are stride-dominant rather than thrust-dominant), most detach well after 3:00.
I don't see the shoelaces facing the catcher as an absolute must. For me, what matters more is what's happening at the hip. I often tweak the orientation of the drag leg to get what I'm looking for in that hip (or hip relative to forearm).