[Bagger Lance]

Assume your water skier has already reached point C. In doing so, he could have arrived there at a constant rate of acceleration, or accelerated to say point B and then stayed at a constant rate. He will never catch up to the boat on muscle power alone unless he had a head start from the other side, or he is very strong. In addition, as he nears the boat he will actually slow down until he reaches his original speed, yet the pull on the rope will be significantly greater than the pull on skier 1. You have to have the arms of a power lifter to stay at point C all day due to the resistance of the water against the bottom of the angled board you are standing on.

When he makes his turn to go back towards point A it must be a sharp turn while keeping the rope taut or else he will temporarily sink into the water. Once started, he won't have nearly the effort of pull as he did catching up to the boat, rather a slight turning of the ski will whip him down to point A and momentum will hurl him over the wake, likely catching his fin on Skier #1 rope and thereby plunging both into the water.

A better analogy might be the water-skier preparing to jump the wake or a competition slalom skier which I once was, but due to the nature of skiing which is essentially a flat board resisting the force of water, I don't think there are parallels to be found.

The Golfing Machine model of the endless belt involves an intentional straight line thrust of the hands to their aiming point, not a literal, ungolf-like straight line path of the hands to the bottom of the swing arc. The intent is another practical application which is difficult to measure mathematically. The actual straight line of the hands can sometimes be seen for a few inches at start down, but it depends on the procedure.