I knew a guy who was a gifted writer ... his screenplays were very Hollywood, and would sell ... he needed to learn experimentation, to push the envelope creatively.
Instead he learned structure and theory, which he already knew. He was a very Hollywood writer before, and they drilled it ten thousand times more into his brain until he became the most boring and banal writer you can think of. Suddenly his scripts were derivative junk, and he'd write terrible endings to all of them which ignored the characters entirely, seeming to say to the audience, "you're stupid, so this is what you're supposed to want" ... rather than what they really wanted.
Cautionary fucking tale. What films need are new ideas. Fuck film school and fuck film theory.