problems than they prevent. Better is case-by-case action, with justification necessary. The establishment of common law based on precedent, if you will.
--In response to the obvious question, Cunc (because I know you worry about this type of thing), my assumption is that it would work this way. I would be involved in (or witness -- I wouldn't feel comfortable locking a page without consulting anyway, but that's just me) an interminable edit war. I would say to myself, "Self, I can see no contributions here, only angry reversions, I think this should be locked till tempers cool and people have something constructive to offer." I would then write a note to the list "Attention sysops: there is a flame/edit/revert war going on at article x. I think it needs locking for a bit. What do you think?" Then, I would wait to see responses. I wouldn't know in advance who would respond. The second person to agree (unless someone disagrees) would perform the lock.
I'd just say we should never lock such articles. That makes the decision-making process much easier.