Nah, I was thinking of multi-round systems, as you can try to vote for a marginal candidate without the net result being a seemingly pretty useless vote in the grand result, because you also have a word to say on other candidates. But then again, maybe not that much.
I prefer preferential voting to multi-round systems. I have yet to see an argument against preferential voting that does not boil down to "Voters are to dumb to understand it. Not me, of course, I understand it fine. Others are dumb."
