I've noticed a couple of times recently interesting discussion attached to a strongly downvoted article or comment. I just thought of a problem description: The display system does not distinguish between interesting/uninteresting items (articles or comments) and interesting/uninteresting threads; an interesting thread is at the mercy of its ancestors.

This could be fixed by allowing items to gain rank in sorting/filtering based on their replies or, more elaborately, a high-scoring reply to a low-scoring item should be promoted above it displaywise. I have no wonderful ideas about how to visually format this.