Most definately the latter...
I mean, we (enlisted-types) arrived at OCS knowing the "game," knowing what limited tools the SIs had to use, how to tie our boots, make our racks, and all the other things that cause the average recruit/candidate to go nuts. At MCRD, everything was shrouded in mystery - "they" wanted it that way. At OCS, all the information was available - it was up to us to take that G-2 and run with it.
I think maturity had a lot to do with it, too - I was just 18 when I went to PISC, but 24 at OCS. I understood that OCS was not a game - it was a professional school that had certain requirements if I was to earn a commission. Yes, the course of the next few decades of my life was at stake during a 6-week period in the summer of '02.
(BY THE WAY - I will be commissioned in just one hour and 45 minutes from now!! 6:00 pm Eastern, 7 May 04!!)
Plus, I feel that each prior/current enlisted candidate had been through much, much worse than OCS during his/her career. Boot camp, for sure...but a whole lot of other crap, too. (I would take OCS over a typical field day from a pissed-off company gunny any day of the week and twice on Sunday!)