Potential provides the whole picture (that is why the opening quote from John 9): it is easy to derive energy, work, force, and even velocity (using energy conservation principle) from it. Newton’s formula V = U/m = — G×M/R ~ m²/sec² still depends on mass M of the attractor, despite V being measured in massless units. On several occasions, we mentioned massless cases of gravity and gravity as time pressure. It is time to formalize that.
We will start with intuitive derivation of potential formula from another Newton’s formula for speed of sound (here it is denoted by c, but we will replace it by s very soon, not to confuse it with the speed of light) :