It might have been too much effort to set up the multi-camera Vicon motion capture system at TED, calibrate it, etc. And unless they put them inside an aviary,

It might have been too much effort to set up the multi-camera Vicon motion capture system at TED, calibrate it, etc. And unless they put them inside an aviary, which would also obscure the drones, I'd be a little worried about losing control of a machine with several exposed spinning blades in an auditorium full of people.