No more would 'swing' in my view, unless you arbitrarily chose to make it so. Inserting a semantically strange and syntactically redundant reflexive pronoun here seems little more than an excuse to justify a needlessly overcomplicated analysis.
Predicate adjectivals, whether 'shut' in the original example or 'unharmed' in mine, serve simply to specify the final state of the subject upon completion of performance of the verb. When the act of returning was accomplished, they were in an unharmed state . When the act of swinging was accomplished, the door was in a closed state.
I suppose one could argue about the precise starting point of the unharmed state just as one could with regard to the precise moment during the swing at which the door went from being open to being closed: the point, while of doubtless metaphysical interest, seems not in any real sense to be material to a linguistic analysis, since both situations are expressed via precisely the same construction!
Why try to make it any more complicated than this??

