I second the first response to this thread. Why wouldn't the real dean use his name and identify his school? By not doing so because of a fear of being mocked because of his school ranking, we already know/assume it to be a low ranking. All he does is lose credibility as to if he IS a dean, and also passes up on a real chance to promote his school. If an actual dean intended to post on LSD, and to give helpful and imformative answers, then using his real name/school would only serve to improve its reputation.
I can honestly picture a thread on the pre-law board "Should I go to X or Y?" "Oh, X's dean posted on the graduate board, you should search the thread. It was really informative and he seemed to know his stuff." Why would a real dean choose to be anonymous when he could be promoting a positive image of himself and his school.
I call either a fake, or a dean without grit to stand behind his comments. Either way, not worth paying attention to, IMHO.