One thing FPTP certainly has going for it is that it’s simpler: simpler to vote and simpler to count. But I don’t think the difference is really all that big, and I’d treat this as a small factor that would only come into play if I couldn’t decide otherwise.
But David Cameron thinks AV is far too complicated to understand:
Here's a passage from a book detailing how the Alternative Vote system works:
"As the process continues the preferences allocated to the remaining candidates may not be the second choices of those electors whose first-choice candidates have been eliminated. It may be that after three candidates have been eliminated, say, when a fourth candidate is removed from the contest one of the electors who gave her first preference to him gave her second, third and fourth preferences to the three other candidates who have already been eliminated, so her fifth preference is then allocated to one of the remaining candidates."
Do you understand that? I didn't. And I've read it many times.
I understood it straight away. Now, Cameron has a first in Politics, Philosophy and Economics from Oxford, so unless he’s been in mental decline since his Bullingdon days, he really should be able to get it. Or, as I suspect, he gets it perfectly well and is just playing dumb because he thinks everyone else is.
That said, the passage is much, much longer than it needs to be. But that’s bad writing, not inherent complexity. Here’s my shorter version:
When a candidate is eliminated, each of their votes is allocated to that voter’s highest preference among the remaining candidates. Preferences for candidates that have already been eliminated are skipped over.
And you could cut the second sentence; it’s implicit in the first.