Technically only when 100% throttle does the same current goes through all of the high current cables.
At partial throttle the current on the Motor loop (B+ to M-) is higher than on the battery loop, Ie at 50% throttle there is almost twice the current on the motor loop than the battery loop as the motor acts as a current source when the PWM is off.
Since we all like to drive at 100% throttle all cables need to be upgraded
