that person is STRATEGIC VOTERS, who are about 90% of the electorate. even if you want to vote honestly, you're still subject to the whims of other voters.

indeed, practically the only thing that matters in a voting method is the aggregate affect of what it achieves in light of other voters. YOUR vote will almost never make a difference. you could upgrade voting methods in exchange for giving up your right to vote, and you'd still be drastically better off.