Originally Posted by
yoko1
If the stab motor was going to stall under an aerodynamic load, it would have happened in the direction of increasing (MCAS), and not decreasing force (pilot trimming)
I believe that you have this backwards. With sufficient positive elevator deflection, there is in fact a net downward force on the stab, resisting a return of the stab to a neutral position (hence the reason for the necessity of the roller coaster maneuvre described in the 737 original manual and taught to at least some pilots back in the day). Under such conditions, MCAS is assisted by aerodynamic forces, while pilot trimming is opposed by the same.