[TChad]

It almost looks as if they, by using the variable tracting point, could tack.

Sure does. I bet that the software that runs this was not trivial to write.

One advantage of this design is that heeling of the ship in response to wind is minimized.

[TChad]

One advantage of this design is that heeling of the ship in response to wind is minimized

As I now see was already mentioned.