My apologies if it seemed that I was contradicting you. You are absolutely correct in that if the primary subject is over exposed an error has been made.
I agree that there are a fair amount of unknowns.
I was just addressing more advanced possibilities to solve the problem; your post provided an easy way to show that.
It is my belief that all to often many of the best options we have to improve our exposures are left at home or in the car. Scrims, flashes, reflectors, filters, lens hoods, spot meters, gray cards, incident meters, shot notes, whatever....
It is of course ok not to use these tools by choice, but it is nice to know they are available.
For me the choice is do I want all my subjects properly on film or do I want to control their exposure in the enlarger?
There isn't a right answer to the question as I see it.
No apology s necessary Mark and no offence intended on my part, I know I can be pedantic at times