John, please clarify: In your generalized W=M*g you specify:
"we must define g to be the acceleration of
the chosen reference frame, relative to an instantaneously colocated
freely
falling frame."
In evaluating the weight of an orbiting astronaut relative to an
earth-bound frame, is the vector g evaluated on the earth surface (and in
the earth surface frame) or at the astronaut's position (and in the earth
surface frame)? I guess I require a specification of the word "colocated"
(to the object or to the frame).