I'm certainly not saying it's the sole contributor, but it's not insignificant. A player could have perfect accuracy finding mafia as town and still lose a significant number of games because they get nightkilled early and people rarely listen to dead players (and they wouldn't have reason to unless they're very familiar with that player, in which case you have the familiarity factor involved). On the flip side, a person could have terrible accuracy and get lynched every game but still win consistently because of the way their lynch consistently influences the information present in the game. If you take the same 12 or so players and have them play 100 mountainous setups and still have people's ratios turn out 1:1 that'd be something else, but it's impossible to setup something like this.
Knowledge is a form of skill imo. :V Skill is a pretty broad term; what else would you define it as? As for having knowledge render your guess as effective as a blind one, seeing as players tend to get "better" or more accurate instead of "worse" over time I'd wager that's not the case. (As for the stock market, I'm of the belief that you can't beat the market unless you get insider tips, so. >_> And mafia is a lot more predictable than the stock market.)
Actually yeah, I misworded that. The correlation of someone who does consistently bad would actually be positive or negative, not zero. :V There's something to be said about being consistently inconsistent rather than consistently bad, but I don't know the numbers involved, so.
