Doug, let us credit Dave for doing the first test of US3987987 figure 5 AWES. All the elements, and in particular the two pulleys framing the skateboard via the tether triangular network, are present. You have to watch the video carefully and make stops to see it all.
I think the rope-drive system is very different as the kite force transfer is made on a single mobile point, as for the NTS linear track. As a result I think the force transfer can be better than that of US 3987987 figure 5 where the kite force acts on the two pulleys simultaneously and within the tether network, leading to a loss of useful transfer as I explained on several previous messages.