I'm not sure about your link question but I wanted to reply to your Dr question.
You're right that there should be NO retraction by anyone other than your son. I'm kind of a shy person too and had a hard time with DS1's doctor. As she was undoing his diaper I would just simple say "please don't do anything to his foreskin" and she ALWAYS would slightly retract moments after I clearly asked her not to. So instead of having a confrontation with her I just simply switched doctors.
I know it's probably prejudges but I searched for a doctor with a foreign name and who had another language listed. I thought if I could find someone who was not American they would have an understanding that most people here don't. And guess what I was right, I love our new doc and he's never even touched DS2's penis (hasn't had a reason to see DS1 yet).
So I know how it feels to not want to start anything with the doc. Chances are he has his opinion about what to do with the foreskin and he's not going to change it no matter what you say anyway so I would just switch. I know you said he's a "friends" father but if you don't see or talk to that person than i don't see how it could be an issue with your friendship and you certainly don't owe the doctor an explanation.
Hi, thanks for coming back to ask a question!
You are correct, your son's doctor should not try to retract his foreskin.
My son's doctor used to do this.
"Belief is not required. Once you know this story
OK, I just posted it for you.