The loads placed on a pylon are much greater for a wake boarder than a 1 or
2 or 3 man tube (yep, you gotta allow for them). A wake boarder only puts a
load on the pylon up to what he can hold. A tube can put much much higher
load on the pylon. Think worst case, as any designer or engineer will. A 1
man tube with a 200 pound person submerging (200 lb person plus maybe an
additional 300 or 400 lbs of drag). Or the same setup being whipped out on a
turn. How about a 2 man? Or 3 man?

I always wanted to do the same to get around the water resistance on the
ropes. But it was not to be.

You might be able to engineer one but the vendors will not touch it I hate
to say.

If you do something, you might consider moving it forward of where you
mentioned to where you see most pylons and towers due to the sideways
pulling load that such a large load would place on the boat.

Good luck and let us know if you succeed ! ! !