[Al Skierkiewicz]

Brian,
Actually adding a third motor isn't as simple as all that. The motors are not efficient so adding the third motor adds another loss into the equation. Even if the motors are running at peak efficiency, they do not approach 100%. If I am reading the graphs correctly, it is between 60 and 70% efficient at peak.
The internal resistance of the battery is 0.011 ohms nominal at full charge. So that means four motors in stall should drop close to 6 volts while 6 motors could drop almost 9 volts. The reality here is that the DSC power supplies drop out preventing any PWM output at around 5.5 volts. The variable is the motor wiring losses and the length of #6 wiring feeding the PD. The longer the run on any of these lines affects the voltage available for the controller and then the motor. Under real world conditions with the average amount of wiring, both Rich Wallace and I have calculated a typical stall current of about 116 amps.
I would think that the CIM motors would be sticking around for a while. Overall they are a decent motor for our use and everyone knows how to mount and use them. (Remember please that these motors are known for having weak bearings and should not be designed to be used with side loads. Your mileage may vary.)