I only got into LiveJournal as a result of being lured into popslash, but I have an idea that the popslash fandom tends to work via personal journals a lot more than communities, when it comes to posting fic, and that most fandoms are balanced differently. Perhaps that gives us a habit of not worrying about precision labelling... because, as you say, those on the flist already have a fair idea what to expect.

I'm inclined to think that a well-done summary trumps everything else, though of course producing a good summary is an art in itself.