RE: Is Traxxas using drill motors?
Lower winding gives more RPM (per volt). Torque is a more complicated thing, but if all you do is decrease winds, the torque at the motor itself is generally equal, but sometimes less. Regardless, you'll have to gear a lower-wind motor less than a higher-wind motor b'cos of the relative difference in RPM vs. torque (if the RPM increases while the torque stays the same, the ratio has gone up, so the gearing must go down to keep it optimal).
The reason for the increase in RPM is the electric inductance / impedence in the coils. When the coil switches into position, it must go from de-energized to energized, and then back again as it switches out of position. If you fix the voltage, the amount of time this takes is related to the inducatance, which is related to the number of winds, the core meteriel used, etc.