There's undeniably a great performance by J. K. Simmons here and this is a film that had me riveted from beginning to end, but I shudder at its message. The fact is, you don't need to be an abusive, homophobic, racist a$$hole and drive those you're teaching to the edge of the abyss to elicit greatness. There are plenty of examples in the world of sports that bear that out, e.g. John Wooden, Bill Walsh, Joe Torre, and Steve Kerr. That's been my experience in other realms as well, like teaching and the workplace, and I'm sure that in the world of music, it's the same. The damage caused to kids by this kind of person, a hard-a$$ wannabe who is really nothing more than a bully, is incalculable, and the film doesn't do justice to that aspect. The fact that this kid (Miles Teller) gets redemption is wonderful; that Simmons's character does is not, in fact, it's more than a little disturbing. The abuser gets to explain himself, show that he's really not such a bad guy, and in the end triumph. How much better would this have been had the kid found a genuine connection to music or his path in life after getting out of that abusive relationship, and we had seen the teacher living in ignominy? Also, since when is jazz about ratcheting up speed to the point of bleeding all over the instrument? Great performances here, but a seriously flawed script, especially in its second half when it could have done something meaningful.