The single overhand seems to be enough when using the band on the Sticht, on the right, the bends restrict the load. When fully weighted the stopper can easily be wiggled, showing little load is reaching it. If I’m going to be using it for a long time I’ll add the second overhand after testing it.
The stopper alone,like on the Michoacán, the left one, needs two, although I’ve used just one for short tests with no movement.
The stopper needs to be completely set, I pull each tail three to four times while massaging the knot to remove all the slack.
Maybe you mean the stopper on the tether, yes will definitely stop any hitch.