Well, the acting is terrific. JK Simmons turns in a wonderful performance as the teacher(you may know him from the Farmers' Insurance ads and a brief TV comedy about a blind attorney)and likewise Miles Teller as the student. Teller is a drummer in real life, and contributes about 40% of the sounds you hear. I will give them that.
The character of Terrance Fletcher is an amalgam of Buddy Rich(as heard on the infamous band tapes excoriating his musicians on the bus ride from their gig for the performance they just gave)and the drill sergeant from Full Metal Jacket. He does have his own brand of volatility, but basically fashioned after those two "warriors".
I could see the writer's wheels turning as he created this character. In the case of the drill instructor, practically lifted him off the page, from the homophobic remarks toward his students('that's not your boyfriend's dick')to the scene where he slaps the student repeatedly to demonstrate the difference between rushing and dragging. In Full Metal Jacket, the sergeant slaps a soldier back and forth to demonstrate the difference between left and right.
There's nothing wrong with combining traits to come up with a unique blend of a character. I'm thinking of the ephemeral young Dell rep- 'dude, you're getting a Dell!' Yeah, that guy! Steven something, who was a composite of Eddie Haskell(the unctuously polite kid from Leave it to Beaver who immediately dropped the manners once the grown-ups were out of the room)and the Keanu Reeves character from Bill & Ted's Excellent Adventure. Never could keep them straight, which one was which..
But I thought that was a marvellous combination: the smart-ass and the air-head. Unlike the practically cut-and-paste job in Whiplash, a subtle jelling. Too bad the actor got busted trying to buy pot. 'Dude, you're getting a cell!'
So yeah, getting back to the teacher(I do digress sometimes!)I thought that was a bit derivative- both the slap and the homophobic remarks. But more than the obvious source material, I had a problem with the teacher himself. With his martial arts methodology. Unless you're training a fighter, striking a student is so inappropriate I don't even know where to start. For that matter, so is brow-beating a student into submission. We see as the movie progresses how this can affect a student even more than the physical abuse of a slap.
The movie tries to take a tone of realism, in the school atmosphere, the conversations you hear, his sense of fitting in with the other students, his attempted romance with the concession girl. All well and good. But from there, everything is hyperbolized-for-Hollywood. The teacher's "tough love", the Herculean tasks he puts his drum students through- and of course the Charlie Parker story.
Okay, I wasn't there personally. But the story goes(at least by all semi-reliable sources)that the cymbal was thrown at Charlie Parker's feet! Jo Jones wasn't trying to decapitate him, just shake him up a little bit.
Every musician has a story where he's humbled in some way- maybe in a lot of ways at once. It happens. Not much fun, but it's part of the growth process. So, again, that part they got right. They just- embroidered it.
My main objection to the movie though, is again the teacher's methods, which of course is the crux of the movie. It's one thing to push a student, but when it becomes emotional and physical abuse, then the line must be drawn. The character, late in the movie, says, "I know I pushed people.But I'm never gonna apologize for how I did it!"
On the contrary, he should apologize profusely for how he did it. He should perform Community Service for how he did it. That sort of behavior is reprehensible. I'm not even sure it belongs inside a boxing ring..
He also says, "the worst thing you can say to a student is good job!" I see what he's saying(I think anyway): that you don't want your student ever to be complacent, but I think you can moderate this--like much else in the movie. If used sparingly, so they feel like they earn it, I think the best thing you can say to a student-when it's warranted- is good job.
When all is said and done, it's about the student. His or her needs. The minute that stops, you've got a problem, Houston. All these histrionics of Terrance Fletcher leave that priority behind and end up being much more about Terrance Fletcher. He's got some serious problems, emotional problems that have to be dealt with before he'd be fit to teach again. Maybe a sequel: Whiplash II, after he's had a year or two of therapy.