I agree with you on this one. Working long overtime doesn't just make you unhappy, it isn't productive either (although I certainly have to grant that it's necessary sometimes). The biggest problem is that it tends to become self-sustaining. You're overworked, so you code something poorly. Then, next time you work with that code, you have to work harder because it's so poorly written.
I wondered about this at a place I recently interviewed where the team said that I'd better be ready to put in 60h/week. I said that I don't think I get more done working 60 instead of 40h, and certainly not better work. They disagreed that it was a problem.
