Even assuming that students in the PT program have lower scores on average, I don't think you can necessarily say that lower scores correlate with less time. In last year's 1PT program, only about a third of the students were working full time; and, among the people whose entering scores I know, the students with the lowest scores were also the most likely to not be working (under the theory that they could get ahead by competing against all the working PT students).

Nothing in my year of law school has amused me more than talking to some of the students who hadn't been working during the school year who are, during the summer, taking 6 units and working full time at externships, etc. They complain bitterly about how hard it is.