Yes, he explains what he is doing the whole time ("riffle off 3 cards with your left thumb, hold a break, ...).
Furthermore he is sitting in front of a mirror, so you can see what's going on from the front and from behind.
I don't know if you know, but he did used to spar with Chuck Norris.
On the DVD itself, to be honest, I was a little bit disappointed. I love riffle shuffle work, and I love RIchard Turner's work, but this seemed to be minor variations of very similar techniques rather than any major contribution to the "Science of Shuffling and Stacking". However, as an introduction to the concepts of riffle stacking, I'm sure it would work well.