it is a wheel driven vehicle, using the wind to turn the wheels.
Yep, it's a wind driven vehicle. However, before you saw the video I think you would swear any wind driven vehicle would never be able to achieve twice or three times wind speed going straight downwind. Am I right or wrong? I don't recall anyone calling it a "sail powered" vehicle. The only thing it has in common with a sailboat is the power source: wind. That, however, puts it in an exclusive group that also includes our beloved sailboats.
It did have telltails, streaming forward at first the rearward as the machine exceeded wind speed.
I know it's not a sailboat and may not be appropriate for this forum, I'm just a sucker for cleaver ideas and the people who see them through.
Will it ever have any use on a boat? Who know's? The future is full of surprises and someday we may find out that everything we know is wrong.