I wish even the "deep" hackers would read these books and realise that command line interfaces and C prototypes are human interfaces too. Yet every time something explodes because someone confused -r and -R on the shell or something equally ridiculous, the internet echo is largely "LOL if you cannot read manpages, then why are you even using computers".

I liked the nuclear reactor example in The Design of Everyday Things because it illustrated (again) that usability is important even if only trained professionals have to use <something>.