The Magic of Reading [Typesetting / Readability] (1999)

As recommended by HN user hollasch earlier today (https://news.ycombinator.com/item?id=29166673#29171772):

> I highly recommend Bill Hill's _The Magic of Reading_, and excellent document on the art of typesetting and why we have various typographic conventions (hundreds of years old now) and why they work. I had so many profound realizations from this paper.