The existence of conversational attractors is why I think any discussion tool needs to be hierarchical -- so any new topic can instantly be "quarantined" in its own space.

The LW comment system does this in theory -- every new comment can be the root of a new discussion -- but apparently in practice some of the same "problem behaviors" (as we say here in the High Energy Children Research Laboratory) still take place.

Moreover, I don't understand why it still happens. If you see the conversation going off in directions that aren't interesting (however popular they may be), can't you just press the little [-] icon to make that subthread disappear? I haven't encountered this problem here myself, so I don't know if there might be some reason that this doesn't work for that purpose.

Just now I tried using that icon -- not because I didn't like the thread, but just to see what happened -- and it very nicely collapsed the whole thing into a single line showing the commenter's name, timestamp, karma points, and how many "children" the comment has. What would be nice, perhaps, is if it showed the first line of content -- or even a summary which I could add to remind myself why I closed the branch. That doesn't seem crucial, however.