"Boxers 50" : for me it did not happen often that my dad came with me to a doctor either as as child or as a teenager, but sometimes he saw me naked when I was washing myself in the kitchen ( we had not a bathing room until I had 18 age) or for my first shower at 18 age in the new bathing room that he had installed in a small workshop at the bottom of a small garden because there was a need to regulate the temperature of the water and he wanted to check it with me
And I remember well of a physical examination for a summer camp at the age of 14 or 15 which was set up by the Railway station in a nurse office ( he was an employed person of the railway society ) , it was a kind of group exam because a large group of about 12 or 15 boys was summoned with a parent at the same hour and we were instructed by a very strict permanent nurse to undress in just briefs alll together as sooon as we arrived and we stand in line againt the wall while our parents, mostly fathers but also a few mothers were sitting on a bench in front of the opposite wall.
Inside the examination room, the nurse instructed to me to remove my brief immediately and so I stayed stark naked for all the examination in front of the woman doctor and the permanent nurse and under the sight of my father.
I was shy towards nudity, so I was embarrassed but a little excited too when I had to walk in the nude in the room to check my spine and gait for instance. As you said, it was kind of a bonding experience, not so bad in deed.
Anyway, at that age, even if it was also embarrassing, I preferred that my father was present than my mother.
I knew by his relations that he was also naked at his mandatory job examinations and when he was a young man at his physical examinations for the mandatory military service and during his time of active duty.
As I became older and closer in age to the time of being summoned for mandatory physical examinations for the mandatory military service, he was teasing at me often about my shyness towards nudity because I would have soon to be naked with a large group of other draftees and in front of a lot of persons at the draft board commision.
So he told me often as he told to Gonzalo " don't be silly" if I complained about his presence when I was washing myself in the kitchen and he stayed in the room to read a newspaper, especially if he saw me putting both hands cupping my balls. I remember that he told me "you will be soon bare arse in front of all the members of the draft board commission for military service and for a long time with a lot of other male teenagers all stark naked".
"Jake nexw york" I presume that when you had sports physicals with your father present, thre was other students undressed also and other fathers who could see you? It was a group exam as for the nude weigh-ins of the team for wrestling.
I agree totally with what you said, if it happened so quickly and matter -of factly, so you were right not to dwell on it. important