High descriptive accuracy, although I don't know if schools are the determining factor (I think you could make a strong argument that the people who go to T14 law schools are already ore driven and competitive and thus more likely to succeed).
Also not sure what to make of their finding of no difference based on school after 5 years... But part of me thinks that the "up or out" culture in law firms selects for people who are going to make it and that after 5 years most of that selection has been done.