There was once a commercial device based on the same theory. Had a Y with hooks on the the two points and a length on the single center point. Even though it hooked at two points, it was the same cross rod, but the old tracks were steel and thicker rubber.. This was also before reverse was common, so you started with the hooks on top of the track, tied the free end to a tree or other anchor, and pulled yourself out. It would also work going forward according to literature, hooking to bottom of track.
Never owned one but gave serious thought to building my own. Never did. Bought a SkiDoo instead.
