I'm kind of wondering this, as well. If we follow the ideas behind the actual game, with breaks down to hat/no hat, facial hair/no facial hair, glasses/no glasses, etc. then any question someone gets to ask should cover multiple players. If, however, people get VERY creative, and you get someone wearing a boa scarf, and someone else has a clown nose or whatever, it opens the door to a very definitive single-player-based question.
Eloh, do you want to set any kind of creativity cap? Or do people just need to realize that the more singular their ideas, the more they may get caught if checked, lol?