Yes. If I remember right, the angle of attack of the propeller blades when this thing is at speed ends up being about the same as that of the sail when the boat's on a beam reach.
To extend the analogy further, I think that the wheel-and-chain mechanism ends up functioning analogously to the boat's keel.
To extend the analogy further, I think that the wheel-and-chain mechanism ends up functioning analogously to the boat's keel.