Theophile! Wow, you should write a paper! Very well put.
The only thing that convinces some people that the idea of engineers endlessly fussing over mixes cannot be true is some pop mixes sound absolutely awful. I have heard mix engineers complain bitterly from time to time about their work turned bad or even given to another engineer to "redo it". Sometimes the producer or the people in charge change things for reasons of their own. Most pop tunes are destined for FM airplay so sometimes the mix is set up for FM and only FM (loudness wars). Many of Katy Perry's top selling songs are examples of that. But some pop mixes turn out pretty good- there's some that are quite listenable. Halsey's Badlands was mastered by Pete Lyman who does a lot of Indie work. Interesting that on her wikipedia page for Badlands Halsey says it lacks a "proper radio hit".
Brad