I agree. I often ask myself if I should write in feedback about things I disliked and come to conclusion that I shouldn't. But, OTOH, when writer read only positive feedback he naturally assumes that he shouldn't try to improve his writing because he writes great stories. *shrugs* It's a double-edged sword I suppose. BtVS fanfiction is so rich and there are so well-written stories that they can be judged by professional writing standards - and deemed good literature. But, of course there is a lot of badly written pieces with heroes wildly out-of-character to feed writer's whimsy.