well I can't tell you if he's Mark in disguise (although I doubt it), and he hasn't asked any undeleted questions.. but deleted questions isn't show to you for a reason ;)
@Whaaaaaat I'm not going to start a precedence by giving you non public information just because you are curious. I am neither implying anything nor trying to hide something, just not setting a precedence. Even if he did ask a deleted question it wouldn't really count anyway, would it?