I joined ARM as Apple's liaison when ARM had gown to ~25 employees in a converted 18th century barn in Swaffham Bulbeck. Dave immediately established himself as "the smartest guy in the room" - he was precise, exacting, and you could trust his answers to be correct. But, he didn't treat his intellect as a club, but more as I'd expect a really good lecturer would- he didn't talk down to you, but spent the time to bring you up to his level. That's a lot of hard work! I don't think, now 30 years on, that I've ever met anyone else like that. I would have liked to have seen him again, but alas it is not to be.