I would agree with two things.. everyone's different, and it is intense.
Some people just absorb information and can readily remember it, others study in different ways. It's all about how you work..
Personally I put the work in every weeknight and had most of the weekends off (except for the weekend before my oral board..and before a few exams). My theory was that if I put in as much work as I could and failed then so be it, I'd tried my best.. but I wasn't going to let the opportunity slip if I could help it by doing a bit more work.
Don't forget too that the pass mark on the theory is 70%, which is what most universities use as their top-grade mark, not their pass mark.. so depending on what you're used to getting in exams you might have to adjust your style!