If you don't think comments are necessary, see how long it takes you to find the sections of this article that deal with exercise:

http://www.lifehack.org/articles/lifestyle/freshman-15-copin...

There are two of them. I found them in under five seconds.

Now find the section of this article that talks about stock options:

http://joelonsoftware.com/articles/fog0000000056.html

Which one took longer? Which one had comments?

QED