I find this fascinating!
My twin sons have non-verbal learning disabilities (i.e., mild-moderate ASD). The longer I have parented them, the more convinced I am their dad is also on the Autism spectrum. It's just that back when we were kids, of course people were only diagnosed with Autism if they were, say, a 10 on the spectrum.
My ex is exceptionally intelligent and a very successful business owner. Yet, he didn't speak until he was 4 and learned to read late. He cannot learn a spoken foreign language, to save his life. He was fine with Latin, because no one speaks that and you can string its words together in a written sentence more-or-less however you want. You don't have to worry about idiomatic usage. Even in English, he says odd things incorrectly, like honestly not understanding the difference between saying "I'd like you to come" to a party and saying "Come, if you want". I think, as a child, he paid attention and consciously taught himself English, the way people learn 2nd languages, instead of absorbing it, the way you're supposed to do with your 1st (and the way fluent people do, with additional languages).
Socially, there are many situations he deals with poorly and has learned to sidestep...although not in nearly as charming and practical a way as your son! For example:
- The other night he dropped off our sons at a movie, knowing it got out so late he didn't want to have to pick them up and drive them home to my house, because he had work early the next morning.
- Yet, he didn't want to communicate with me about picking them up, because he knew I don't let our sons hang out with the kid attending the movie with them.
- It makes him very anxious to think about telling our sons "no", or to have me tell him he should (when he knows I'm right).
- So he waited until shortly before the movie let out, called me, and made it sound like he was just double-checking that I was picking up the boys. Of course, I had no idea what he was talking about. He said he thought they had called me and gotten my OK about seeing the movie and having me pick them up. (Well, our sons usually tell it like it is, because they have few diplomacy skills. It turned out he never discussed with our sons asking me in advance, to pick them up. When he dropped them off at the theater, he said, "I'll pick you up, but if I don't, call your mom and have her come get you.")
- I told him sorry, I couldn't help. My little one was asleep and my husband was out, so I couldn't leave to get our sons. He'd have to get them himself.
- He bristled up and sounded self-righteously angry, going on about how unfair this was to him, because he had to work the next morning. When we were in our early 20's, I probably would have caved in and done what he wanted, so as not to fight and because his unexpected anger would have made me wonder if I were looking at the situation wrong (...Was I at fault?)
His tactics to avoid social / conversational discomfort don't work well on me anymore, because I'm much more clear when I'm not at fault, and I don't care if he's unreasonably angry. I don't have to live with him. But I sense that these things work very well with his wife. She puts up with a lot of grossly inconsiderate behavior (mostly not communicating with her about schedules) that I would not tolerate.
I'm pleased to hear that your son has consciously translated an aspect of human communication that doesn't come naturally to him, and learned to use it in an effective way. What a relief it must be, for you to know he can do that! Yes, it's sad to see our kids have exhausting challenges. But we all have some - visible or not. What a triumph, when you figure out how to make accommodations for them, and thrive!