Three geese, one brown two whiteDespite the crushing referendum result last week, there is one place AV will never be displaced – when politicians choose one of their own. It’s not just Labour – even the Tories do it. Sure – it’s often done differently, round by round, to allow some very sophisticated game-playing (although that doesn’t work when the membership get a say). When the Tories chose between IDS, Ken Clarke and Michael Portillo, the IDS crowd lent their first round votes to Clarke because they knew a) that their guy would make the next round and b) Ken Clarke couldn’t win.

And you can see why they use it. Candidates with a narrow support base (like Clarke in 2001) would come through the middle, especially if two similar candidates stand. You get to express all your preferences. You can vote sincerely throughout (although as above, spreading it out over several separate ballots allows a bit more gaming to come in).

Today Holyrood will use the same system to elect a Presiding Officer. We have three candidates who could almost have been designed to demonstrate this principle. Two fierce SNP women, Christine Grahame and Tricia Marwick, plus Hugh Henry, a dry but impressive former Labour minister. Christine declared first, and without iterated run-offs, that would surely have kept Tricia out. Instead she’s surely going to win.

Assuming for the sake of argument a degree of voting by party, which is unfortunately pretty likely even for a notionally non-partisan role, and assuming the rest of the tattered Yoonyonisht Conshpirashy back Hugh, it’s easy to see how he could win. Yet there can be few in the Chamber with a first preference for either of the SNP candidates and a second preference for Hugh.

The fact remains, as the AV campaign should have said, preferential voting remains the only sensible way to indicate opinion and count votes when electing a single candidate (fans of various obscure Condorcet mechanisms please take it up in the comments). And as should be obvious, there’s no good way to elect single candidates and achieve proportionality.