i'm now sure how one is supposed to stop being a perfectionist when one has advisers and mentors who expect ones work to be perfect. to all extents and purposes anyway: one can quibble about infinitesimals, but the fact of the matter is that once you reach the 95th percentile you're so far along the exponent that you may as well call the standard perfection. you read all these articles about how to get anxiety under control, that a thesis that's good enough is good enough, and so on, but none of those things seem to apply to me, or to other people i know who are getting phds worth a whit. the real test for us seems to be how to live with the disappointment.