I would think the flash stand would either attract the signal or mes it up and absorb it. I guess it doesn't function like an antenna. That last shot is awesome.
I've always wondered that if somebody could make a really tall lightstand that won't tip, you could light from the skiers level. That's never gonna happen.
What different would it make to light from the skiers level? To control light spill on the deck of the jump? You can always get rid of that by using grids or different reflectors. I just chose a wide refector because I wanted a bit of spill on the deck.