I read this thread a couple of days ago, and I have been mulling over it ever since.
The writer-reader relationship is delicately balanced in fanfic. One aspect I love about fanfic is that no money is involved. The writer freely gives his/her stories for anyone to read. The reader 'pays' by becoming involved in the story the writer is creating and giving comments.
I understand the disappointment when a reader commits to a story only to have to accept that the story will not be finished. However, the writer has already committed far more time and emotional involvement to the story than the reader has and is probably just as disappointed that the story wasn't finished. The difference, of course, is that the reader has very little control over getting the story finished. The writer might not have a lot of control, either, but has more than the reader.
Commenting on stories, even with the risk of them not being finished, is not a waste of time if you value fanfiction in general and this fandom in particular.
IMO if a significant portion of readers decide to comment only once a story is finished, the fanfiction part of this (or any) fandom will die quickly.
If, as a reader, you don't like something about the stories being written and posted (too much angst, not enough angst, characters not acting in character, too short, too long, too light, not light enough etc), why not write a story you would enjoy reading? Reading but not commenting contributes nothing to this community. Having strict and inflexible 'demands' that mean ditching most stories after a few paragraphs doesn't contribute much either.
The fact that we have more comments in this thread than many (all?) stories being posted is concerning, and possibly says something about the current health of LnC fanfic. Ultimately, the community will only survive if enough people care enough to make a contribution as a writer or a commenting reader or both.
