I think you guys are missing the point. All the helium does is make your kite slightly lighter. bugger all lighter. It will maker it slightly more efficient, powerfull and turn faster. but only by a very small portion.
It wont stop the kite from diving or flying across the window and the kite does not have "buoyancy" to make it float unassisted.
its simply a little be lighter. in normal practical terms its a pointless exercise.
if you are racing it out for gold at the Olympics In years to come and every one uses the same kite and board and your race success or failure is measured in milliseconds then using helium to reduce kite weight make the tiny difference that enambles you to win all other factors being equal.
no, not missing the point. totally agree with you for day to day it´s pointless
but still wonder how much of an advantage would be for the race guys - just a few miliseconds or something more valid....?