Interesting... I had a professor who spent a ton of time looking at my code. I almost didn't like asking him a question, because before he'd answer it, he'd insist on reviewing at my code and making me refactor it, and it was always at least a half hour, often well over an hour, before we'd actually get to my question. It was good for me, though, and I knew it - I did ask him to be my senior thesis advisor.

Interestingly, this guy was a math professor, not a CS professor. But he was very particular about code.