w8coach, first lets start by saying a lot of the time with Dr. B's interviews, there is no follow up questions in order to get more in depth answers. Or none is provided by him. In my experience, he just needs to be prodded a little more!
I assure you if that line of questioning had been taken a bit further, he would have said what is most important concerning the center pivot is in fact the hip. The right foot can turn all day long, and the hip could lag behind. The foot does not produce the separation/force needed in the throw. Depending on the athlete, the right foot may or may not turn as a result. But he does NOT coach it.(I used to coach exactly how you described your contention with this topic. I don't anymore)
Another example may be with Yuri. I was apart of a clinic a few years ago and a coach asked him how he thinks about pushing the hammer. Yuri's answer was of course over simplified leaving the guy with even more questions. He didn't understand, why wouldn't you think of this, this, and this when trying to push? Yuri said "when you eat, do you think of your arm, your shoulder and core while you put the fork to your mouth? I only think of hand" This isn't an exact analogy, but it can relate in that you can't sweat the small stuff! The arms, feet, knees, etc are all inconsequential when compared to the large muscle groups that actually produce the forces to move the implement. -Kibwé