That's great that you keep in touch with him -- good one!
It's amazing how, no matter how old we manage to get (speaking for myself here), there is always someone who has a wealth of different experience... your story reminds me of when I taught my first ground school classes, in a formal setting.. at a technical college, part-time.... I was a nervous kid and wanted SO BADLY to do everything RIGHT...
I always started out my new courses with everyone taking a moment to say why they were there, what kind of flying they liked, you know... it worked wonders to get people visiting, but it also helped me to try to figure out how to teach things.
My first class was always "Basic Aerodynamics", and so imagine my chagrin when the polite gentleman sitting right in the front row, dead center, up by me, said he was a retired aerodynamicist from Boeing, and had been there 34 years...... I would have given anything to been able to drop through a hole in the floor, and come up in Samoa or somewhere.....
But, he was a gracious person and we all survived just fine.... but, it was a big reminder for me to "check out every teeny thing before you say it".