[dragonwriter]

> This is, at the end of the day, mostly semantics but you can't have proportional representation, in a vote that only elects one person.

Proportional representation is really a matter of degree rather than a binary categorization -- a system doesn't magically become proportional when you apply it to a two-member constituency that would be not-proportional when applied to a single-member constituency.

OTOH, the maximum degree of proportionality you can achieve in an electoral system increases with the number of seats that are elected by the same set of ballots.

STV is an election method defined for any arbitrary number of seats, IRV/AV is exactly STV applied to a single-seat election.