I am ever so grateful to Bill Westmiller, whose comments are marked "BW: ". The quotes marked TSW are from "The Scientific Worldview" and my comments are marked "[GB: ".
"All bodies are subject to divergence [from] and convergence from [with] other bodies."
“Entropy: A thermodynamic quantity representing the unavailability of a system's thermal energy for conversion into mechanical work, due to lack of order or predictability; gradual decline into disorder.”
Whereas, a good explanation describes the process:
Entropy: The proposition that objects in motion tend to collide and bounce away from each other.
BW: Obviously, the tendency is more pronounced in isolated systems, where the bounces spread out until they achieve the maximum common separation, resulting in equilibrium.
BW: As you point out, the terms "order" and "disorder" are subjective. An isolated system in equilibrium is "well ordered", not disordered: the matter in motion is "perfectly" balanced. The A-B containers are both "well ordered" systems in themselves, until they are consolidated by opening the valve, creating a "disordered" unity, for a little while.
BW: That doesn't solve the quandary of why objects in motion would *not* be inclined to always bounce *away* from each other and why they tend toward maximum common separation. I don't think your treatment really answers that problem.
BW: To the particulars:
TSW: "Only by assuming complementarity can we resolve the contradiction between conservation, which assumes that the universe is eternal, and the indeterministic interpretation of the SLT, which implies that it is not."
BW: I think you mean "infinite", rather than "eternal". If the universe is finite, then the objects in motion in our cosmos always have a "better place to bounce" (the void) and will never maximize their separation: entropy rules. On the other hand, if it is infinite, then the universe is - and always has been - in a state of optimized equilibrium: maximum separation has been achieved (subjectively "well ordered", conventionally "disordered").