I don't think she said he couldn't beat Schneizel in chess, I think it was that Schneizel was Lulu's most difficult opponent. She was comparing Mao to Schneizel at the time (though she didn't realize that the person Lulu was "playing" with was Mao). So I think that just forshadows that Schneizel is going to be one difficult bastard to deal with. Though he does seem like a pretty nice guy so far.
(no subject)