(lens) motors require torque to move lens elements
motor torque is related to voltage
increase the available voltage, increase the motor torque, speed up lens drive
Thats definitively wrong. Canon uses USM motors and the torque of this motors isnt related to voltage.
I cant imagine why a higher voltage should accelerate a USM motor.
So, one the one hand I'm definitely wrong, but on the other you can't see that I am definitely wrong. Can't have it both ways.
A USM motor causes movement by setting up an oscillation. The amplitude of that oscillation could be a function of available drive voltage.