I have read many post about finless boards. Surely they work, but the real question is: Do they work better?
I think not. Fins has a role, they add tracking, directional stability and maybe some drag. The "always on edge" argument is not so true at kiteboarding, many times you ride the board flatter and as the sport is about air, fins are a big help when landind.
Fins are good for carving turns too, so a necesary for wave riding. Look at nature, fish have fins, some of them are for power but others are there for tracking.
Look at the aircraft industrie, planes have wings but also have "fins" for stabilization purpouses. The most technological advanced aircrafts are getting appart of this stable designs but they have a powerfull supercomputer onboard to stay in the air.
With a finless board, you have to be the computer, making unnecessary adjusments all time on how you ride the board.
Fins are here to stay!! (in fact they are getting bigger).