@mathew wrote:
I'm not talking about censorship; I'm talking about systems which represent discussions as a tree, make that tree of comments visible to the user, and provide tools to follow or not follow individual branches of the tree of discussion.
Like Usenet in the 1990s, for example, with threaded newsreaders. If someone went off on a tangent, I could junk the thread and not see any of the rest of the discussion. If I was deeply interested in the tangential topic, I could have my newsreader automatically select any new posts that were in the tree of posts resulting from the tangential one.