In June 1969, John E. Warnock achieved a milestone of sorts at the University of Utah by producing the shortest Ph.D. dissertation in the university's history.
Warnock, who died Saturday, was one of the leading computer scientists of his era and co-founder in 1982 of Adobe Inc.
I agree on what you say about the ways PDFs are used today, but back in the 1982 the world was different. Back then it was a useful thing imho.