RE: Tether
I am not sure what you are talking about.
As far as breaking a fall, these may help you out.
[link]http://www.shorelinemtn.com/store/prodinfo.asp?number=QD-5006&variation=&aitem=15&mitem=23[/link]
These are actualy for rock climbing.
Will help if you fall out of the stand, and can' t handle the jolt (if there is one). I wouldn' t know, never fallen, and don' t wear a safety harness, so I hope I don' t fall.