I wasn't actually involved at the time but I was told later that the reason in post #19 by Dominator2:
"As Fred did not trust anything automatic, he moved the wings and slats manually, but without the system disabled. Within a couple of weeks the jets were grounded as the follow-up motors were screwed (a technical term)."
...is closer to the mark. As confirmation its worth noting the Saudi ADVs had no issues with AWS as the default option.