Reminds me of how awkward HTML doctypes used to be. Nowadays it's very simple, but in the past? You had to refer to the URL of the doctype declaration on every page

> <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">

This plus the X-UA-Compatible stuff mentioned in the article meant that for many people, the first few lines of code on a web page were something they probably copied from a tutorial or reference document every time, at least if they didn't have a CMS handy.