I agree on this. But, see below: The same wrong way of thought as what you did before (when you talked about accelerating rocket). A reference point for velocity must be an inertial reference frame. Earth, in this respect, become a non-inertial reference frame and therefore should not be used as a reference point. Picking a fixed point such as the origin of the objects (or the system center of mass) would not yield any differential of velocities or acceleration. That's why I said, you had picked the wrong reference point in your assessement.