You could also argue that elections are the mind-killer - if the popularity of opinions among the population had little or no impact on who got in power, people wouldn't get worked up as much about them. I wonder if the republic of Venice - with it's mix of elections and random choice - had more or less factionalism than modern western societies do (I would guess it wasn't as widespread as ours, a bit like most Chinese people don't have strong political ideologies, but the educated are more likely to).

For similar reasons, you could argue that karma on lesswrong (and reddit) is a small mind-killer.

If you went to your polling place and saw a list of candidates, none of whom you'd heard of before, you might rightly refrain from voting and polluting the signal with your noise. Knowing party affiliations makes people think they have enough information to vote.

That's because knowing party affiliation actually gives you some information about the candidate (the more parties in the election, the more information you get).

If you want to know what kind of policies candidate Joe is likely to enact, you'll probably get a better guess by looking at which policies were enacted by candidates of the same party as candidate Joe, than by listening to his speeches (which are likely to be mostly filled with platitudes and applause lights).