The reflex strap is pretty neat.
I think that the inline skater (not hooked in, note ) in the "record" video was happy that it flew away when he blew it. It flew very efficiently on its own (and quite dangerously too). Flying away probably minimizes damage both to kitewing and pilot.
A deadly effect with towed hangliders is "lockout" where increasing sideforce makes it bank further increasing the sideforce etc. The wing-in-ground effect here would help a bit but when a glider goes you have got to go with it. No way to unhook in that situation.
A good agent might post some water crash videos (hint) just to show how it can be safely done with a leash.