Transmitting Mechanical Power Down the Tower

I always wondered why nobody ever tried to put a HAWT gearbox and generator on the ground rather than at the top of the tower. I always just assumed that if I were a mechanical engineer, then I’d know that the numbers just don’t work. But then it occurred to me that this is exactly how the Darrieus rotor’s power gets to its gearbox and generator. Of course, only half of the torque comes from the top of the tower, but still… it got me to wondering if it might somehow be feasible to put the HAWT gearbox and generator on the ground. And my elementary school teachers always assured me that there’s no such thing as a stupid question, so…

(bear in mind that these same teachers would always ask me if I wouldn’t like to spend a month of my summer vacation coming in for English grammar tutoring so I could get a hundred points of extra-credit…)