Tom Weller's Culture Made Stupid nearly did me in. I was working as a literary criticism reference series editor at the time, and what got me was his footnote that said (approximately) "All quotations from Shakespeare will be from the edition on my shelf -- the big one, with the pink cover."

My cousin Joe, who's a professional actor and singer, had the same reaction to the passage about how opera had brought something new that Western theatre had hitherto lacked: Fat people bellowing in foreign languages.

CMS's chart of proofreader's marks, and what the indicia on copyright pages really mean, went up on bulletin boards all over the industry.

Tom Weller is a genius.