Michael Bishop said it best "it's hard to do jiu-jitsu when you are getting punched in the face." I infer that he was referring to sport jiu jitsu and not the kind of self-defense jiu-jitsu that Rickson and Royce practiced.

Bas Rutten said something to the effect of "If I can fight with rules, do you think I can't fight if I took them all away?" I think it has to do with intensity. The GJJ class (combatives) starts out pretty chill and gets you to learn the techniques. The GC class doesn't have intense warm ups and rolling. Sport type BJJ classes are physically more intense and guys start rolling right away. Most GC guys probably couldn't perform very well (initially) in a more sport type competition BJJ class.

80 classes for me will be 10 months worth of bjj. thats a long time before i am allowed to roll