He has basically created a 3:1 Z-rig without the use of pulleys. The system will work for short distances, but as already noted, there is loss of mechanical advantage due to the rope on rope friction.

Rope on rope is not ideal, but we utilize this method when creating static back-ties on questionable anchor points such as small trees, poles, etc. We tie the back-tie line (high up, as well as the main or belay line – generally you keep you anchor points low to create sheer force instead of lever force, but when back-tying high, the vector forces will be directed downward) to the tree/pole, place a butterfly knot in the line about ½ back and then run the line around the base of a smooth, but sturdy tree/pole and take the running end back through the butterfly, thus creating a 2:1 mechanical advantage.

Pete