Originally Posted by Benny Profane
"In my experience photographers don't mask things into separate layers when they were shot together."
In my experience, photographers haven't known squat about retouching (no, I take that back - some know just enough to be obnoxious about it), and, even less today, because they rely so much on "Hey, no whoop, we'll just fix it in post".
In my opinion that's a bad thing. Having some real knowledge of the process helps to minimize downstream costs and meet deadlines. It helps to know what details can be easily adjusted in post compared to what carries a high tradeoff between quality and time required. If you don't understand it, it's also way too easy to overdo things. Things like excessive curves as a means of boosting image contrast just create so many problems.