To the engineer however, the distinction between extracting an isolated
signal which is independently signaled versus the synthesis of a derived
signal which is not explicitly and discretely separable are two entirely
different methods. The fact that the human brain can be fooled to think
that the more complex discrete version can be adequately imitated by the
less complex derived version really doesn't change the technical
distinction between real versus synthetic.

I never said it did. I object to the term "synthetic".