But then why does every single one of the engineers who have worked with him report that he's the single smartest person they've ever worked with?
If you read the biography, there have been times when an engineer has said "I can't meet these requirements," and he said "Ok, I'll do your job AND my job, and I'll get it done." And he did.
I think anyone believing he's not an extremely talented engineer has not read much about him.