Forces on propeller

Question from @Dream to fly @ATVpilot Have another question about propeller twisting force, one is called the aerodynamic twisting moment (ATM), another one is the centrifugal twisting moment (CTM). I heard ATM drive the propeller to a coarse pitch and CTM drive the propeller to a fine pitch. Why is that happen and how they affect the propeller in-flight? I think ATM is the dominant force of a single engine aircraft variable pitch propeller and CTM is the dominant force on the propellers of the multiengine aircraft. It is because single engine aircraft's propeller tend to stop the rotation in a fine pitch after engine shutdown to facilitate the next engine start up and multiengine aircraft's propeller tend to stop at a coarse pitch after engine shutdown to reduce the drag in case of single engine failure inflight/ during takeoff.