I agree, these modules are pretty unhelpful without some basic explanation around how the ball is made. Nicholas Yang did some hard work last December to fill the gaps left by CGCookie - you'll find it here:
https://drive.google.com/file/d/0B61Z1wMgyCh9XzFBMjl4bi1oejg/view?usp=sharing
thank you stephen and nicholas. i totally agree that the course badly needs an explanation of how the rig is made or at least a pointer to another course or video that explains it.