In the Advanced Compass Setup Document , under CompassMot Calibration details it says if magnetic interference is higher than 60% you should try moving
your APM/PX or External GPS/Compass Module further up and away from the sources of interference.
So the CompassMot is only for monitoring not Calibration, just like Battery Monitoring.
Finally in my opinion , the CompassMot Calibration should be renamed as CompassMot Monitoring.
Could anyone argue or disargue with my opinion?
No, it is calibration. And it does compensate in flight based on those calibrations. The 60% statement is telling you that is a problematic level of interference that you need to fix.
That should be set to 2 presuming you have a power module that is measuring current. Without a power module that measures current, it would be 1 for throttle.