Without having looked at any wiring schematics for the iSight module... does anyone know if it's even possible to apply power to the iSight hardware module, without the LED becoming illuminated?

I would presume the LED is wired directly to the module's power. Then, it would be physically impossible to turn on the camera, without the LED becoming illuminated. (And, in my opinion, obviate much of the need for these silly stickers.)

It would also be an odd design for Apple to make the camera's LED indicator an independently controllable component.