Side discussions for increasing signal-to-noise

Found this over at the Planet GNOME pages, which seems to have similar bearing on the problem with lists:

Rather than fragmenting lists by "general topic", which seems not to work, why don't we fragment list traffic on a per discussion basis. Very few discussions will need this, but the few that do we can not destroy the public list's readability for the week+ it takes to run its course.

Seth Nickell: A Listy Dilemma

A solution for implementing Seth's idea (which were based around the same signal-to-noise issues that I thought of) would be to use QuickTopic.