I understand the lever changes the governor on the CSU. What's being governed ? It can't be RPM because otherwise it would be calibrated with RPM.
Perhaps I don't get your question here, but this is
exactly what happens. You
are governing the prop RPM. The CSU increases or reduces pressure in the hub to change the pitch of the propeller blades so that the propeller balances the engine torque thus producing a fixed (constant) RPM....
