Physicists don't use the word heat to mean entropy.
2.
The OP used the term heat meaning infrared radiation, light is heat only when heat means entropy.
3.
I suppose that when a system of higher entropy is joined with a system of lower entropy that entropy does not move to create a more uniform mean entropy in the joined system.
4.
It would mean entropy would be introduced from a phenomenological POV, which is not my favoriute POV, but if he is willing to spend the time to do a lot of writing, why not let him do that?
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