Agreed. I comment at the beginning and end of all majr layout sections, and in other places where needed. I work a lot with jsp pages, where there is jstl login in place within the file, so often I comment those sections to explainthe logic as well.
All of this is largely because I work frequently in a team on one project, so there is a good chance that someone else may have to do something with my work.
I also like to comment javascript fairly thoroughly for the same reason (and to remind myself of what I was doing in the future!)... It just seems to make sense to me to provide a plain english explanation of what is going on in a script for the uninitiated.
David
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