renaissance poisson

I think that part of the problem is that we are poorly served by our tools. Any decent USENET reader will allow you to navigate subthreads easily and prune any which are not of interest to you. That makes it less of a concern if 60% of the posts are on a digression because you can easily ignore those and focus on the relevant bits.

While it should be possible to produce something even better than that in a graphical browser window, every web discussion forum that I've seen is far less capable than the old text-based USENET readers. Although DW/LJ do provide threaded discussions, it's pretty much all-or-nothing, so a 60% digression really does derail any other topics of discussion.