I couldn't even read that site. Had to copy/paste into Word.
Anyway, this is what I think he's trying to explain:
Please excuse my poor drawing skills. Clearly not to scale.
Anyway, the rope is in yellow and the areas circled in red are the rope behind the ring. The rope behind the ring is the part that should be in contact with your neck. I believe the idea is that this replicates knots that would ideally focus pressure on the carotids, and the use of the ring is to avoid pressure on the trachea.
No idea whether this would work, but I think it's what he's trying to explain.