All throughout flight school as well as with my twelve flight reviews so far, I have never heard the term "power settling"! The only place I have ever heard that term is on the internet from old military pilots.
As for the condition of "power required exceeding power available", that is brought up during the SFAR 73 discussion of rotor decay, low-rpm rotor stall, low-rpm recovery, and power management, but has no name for itself.