I may have been overpessimistic. I didn't think about the separate feeds, and you're right about that making things easier.
There might be questions about who has the "right" to be speaking at a given moment-- that would define what constitutes an interruption.
Need it be more complex than: person A begins to speak while person B is still speaking? It might get a few false positives, but it should be a useful metric overall.
Sweet, there's another Bloggingheads episode with Eliezer.
Bloggingheads: Robert Wright and Eliezer Yudkowsky: Science Saturday: Purposes and Futures