Originally Posted by lomiller
In other words, if you radiatively decouple the atmosphere completely from its surroundings, so that it can only absorb and release heat through conduction, then blackbody temperature of the surface is your only constraint. Well, yeah. But that's an irrelevant scenario, with or without greenhouse gasses, because that doesn't describe the atmosphere of any
No. Adiabatic lapse rate
is a function of gravity and constant-pressure heat capacity. Surface temperature is part of the boundary condition for the problem (as already pointed out, this lapse rate won't hold over the entire atmosphere), but you're confusing boundary conditions with the solution to the problem.
And yet, your attempts to describe what's wrong with what I said are incorrect.