It seems to be common for the more extreme autists not to know their own strength. A relative of mine had a baby when she was ancient, and he has fairly serious autism. She managed him pretty well when he was small, but, once he was a teenager, he started (often unintentionally) wrecking shit. I personally witnessed him put his fist through a door, and, these days, their house is in shambles. She doesn't bother fixing anything unless it's vital for the house because she knows he'll destroy it eventually.
I worry what's going to happen to him when she dies. She's in her 70s already.