In a comment on Signs you're a crappy programmer Philip Storry said:

One of my favourite quotes from Ken Thompson (who apparently knows a bit about computers) is:

I tend to break up a subprogram when there are too many local variables. Another clue is [too many] levels of indentation. I rarely look at length.

It's not an absolute truth, but he does give two pretty good indicators.

The length of a function isn't important - what you're trying to do in that length is... :-)

This kind of quote used to make me disappointed that I never went to university to do computer science. I imagined that such quotes would be thrown out by a teacher, followed by the magic word "Discuss".

Of course, I eventually met some CS students, who disabused me of this romantic notion. ;-)

Yeah, that would be a neat class, but I never had a class like that. It's not so much the teachers wouldn't be open to that, but that the students wouldn't be capable of following up with a discussion. It would be dumb anyway -- speculating on design practices that apply to something none of the students have ever done: working with code at different stages of the code life cycle. At best the students could rephrase other bits of wisdom heard but never experienced, which does not a discussion make. This describes a large portion of the discussions I had in college classes. Discussion sucked. But then I wasn't a very satisfied student in general.