Slide 3 talks about using your "core," muscles and rotating around the spine.
The point of posting the slides was to show the position of the paddle through the water, and when to exit, considering that it's been a big theme in team practices: getting in up front, and getting out early so as not to drag on the boat.
These slides were excerpted from the book, as I mentioned, which goes into all the detail you described, and then some. It just wouldn't have been practical to re-create all of that on this board.