I believe that his theory on class attendance was two-fold:
1) Attending class would take time away from those activities on-which you should really focus (learning black-letter-law and working HYPOs)
2) Attending class will tend to confuse the average 1L because many professors tend to waste class-time playing "hide-the-ball" and talking about policy rather than "black-letter-law". This wouldn't be a waste IF they actually tested on policy-theory, but most law exams test black-letter-law.
I'm not sure that he's correct in his assumption that you can skip class and somehow be better in-tune with what the professor will expect on a final exam, but I think that Aticus does provide several good suggestions for prep materials in PLS2.