You can’t “double your vote” in Australia

On Sunday 2007-08-20, Steve Dalton of the Gold Coast Greens posted the following:

Reposting this excellent cartoon that everyone should see to get an understanding of preferential voting and why it is so important to Vote 1 Green!

Except, of course, it isn’t actually doubling your vote, is it? The ‘S’ in STV is of integral importance to representative democracy: each voter gets a single vote. The Greens do nothing towards increasing constituents’ understanding of our electoral system with phrases like ‘double your vote’; how does this differ (other than in the side of the political watershed on which it falls) from ‘don’t waste your vote’?

I think that the original ‘double your vote’ campaign was (is?) about getting other Americans to enroll (and then, I guess, getting them to vote the same as yourself). At any rate, that’s what the www.doubleyourvote.com website is about.