I added somewhere around 10 pounds of muscle from the early stages of CC, but I was really skinny then. I've added another 10 pounds after I started lifting weights too, but I think it could be done without the weights.
I do some grappling on occasion, and I find that I'm able to muscle almost all of the other grapplers except for two or three. I'm beating or staying even with far more experienced guys that I have no business beating, simply because I can muscle them around a bit.
TLR YES!!! Get it, you won't regret it. Full-body workouts, logical progression, clearly laid out... it's been great for me.