@Reaces I think the issue getting muddied here is peer-review as a system of knowledge rating and verification - if peer review fails, for any reason, you can no longer derive anything from whatever is left as you can no longer rely on the knowledge to be "true". Accepting an answer, above all else, is a clear indication of the truthfulness/helpfulness of an answer. If that goal can't be reached, what is the point?

How about autoclosing any unanswered question whose owner has left sf, as such q can never get an accepted answer?