For three years, John R. Lott Jr., the controversial American Enterprise Institute scholar and author of "More Guns, Less Crime," has used the pseudonym of "Mary Rosh" to post defenses of himself on the Internet. "Rosh" described Lott as a meticulous, non-ideological researcher, and even claimed to be one of his former students. "I have to say that he was the best professor I ever had," Rosh gushed in one Internet posting.