Not impossible.
If the clone is pumping a higher voltage to the motor, or able to maintain a higher voltage at full speed, then it could be faster. Also, if a clone is lighter than the bit, it could gain a little there too. Remember, dual battery mods make cars go faster.
Heck, if the battery is closer to the front wheels, it might even steer a little better too because of more pressure on the wheels.
Now, whether I believe that is actually happening in this case, that is another matter
