[Evisse the Blue]

On the topic of all fanfic being non-canon: I cannot agree to such a simplistic view; it's like saying that every one of us is guilty because of the original sin. Some are more innocent than others, and that's how some fics are more canon than others. As for not being able to guess what a character would have thought in a certain situation: that depends on a writer's psychological insight. We all make guesses about what goes on in each other's minds, and the better we know that person, the more accurate these guesses are.
When I read a fic that's well-written and does not stray from canon, I get a feeling of authenticity, while when I read a well-written slash fic, for instance, (to get back on topic), the feeling is that of frustration and confusion. And that's not because I have something against slash (slash fic directed at other fandoms in which slash is conceivable is okay, slash fic in Tolkien's world is like puting an elephant in a china store).

I realise how this debate may turn into an endless reiteration of divergent opinions, so I'll try to stay away from this topic from now on unless I think of some really strong arguments to prove my point.