I don't know about snow kiting and split boards, but even with a regular snow board in the resort, if it is too icy, it can be very difficult to control. I've done it several times were on a stepper hill and you edging hard, then happen to hit an icy spot, then the board just leaves the ground and you travel down hill for maybe a metre. Recover if lucky, crash and cartwhell if not!
Re directional snowboard, i still think that could work for snow kiting, just as a directional board, eg Stonker works for kite boarding. I've got nothing to base that on other than just my thought.
Christie is spltting hers at this very moment, so will be interesting to see how she goes.
EDIT - blonde comment above re directional. Thought about it last night after posting, and think i've realised why directional snowboard wouldn't work so great. Stonker has 2 "sets" of bindings to ride heel side each direction - on the snowboard, you're kind of tied into the one binding so would be riding toe side back. Which i guess is the ultimate aim, but probably not easy for beginner.