In a normal rocket, the speed you calculated is half the exhaust speed, not the speed of the rocket.
Power = (1/2)*(mass rate of fuel use)*(exhaust speed)^2
Force = (mass rate of fuel use)*(exhaust speed)
Power/Force = (exhaust speed)/2
Rockets are also machines that give a constant force at constant power, but both of these are constant because the exhaust velocity is constant. For the EM drive, if it really has no exhaust, then all these equations go out the door since momentum is not conserved and that means all calculations are inconsistent with our current knowledge of physics. "Over unity" no longer has any meaning.
I'm still waiting to see what happens.