One thing I noticed is he is not letting any grass grow under him. He positions and cuts 3 sheets during the 30 sec video. He appears to have the positioning down pat as well. pushing the edge to the constantly spinning cutter wheels right at the center of that edge then almost imperceptibly giving it a nudge with his left hand as the clamps the center down with the right. I shudder to think of how many disks he could cut in an hour given an endless supply of sheets to cut. Another thing that I find intriguing is how easily he seems to not only separate pick up and position the sheets. I don't see a robot being able to do it as fast or as accurately