[smashface]

This is a much better example of the point the author was trying to illustrate.

Though I'm not sure sure if the HTML / TeX comparison is the best to exemplify the concept. I feel that if a beginner were to make the conceptual mistake that HTML tags are not nested that they may also not grasp that {}'s are to be nested as well. Thus falling into the same trap as HTML.

I'll admit that {}'s look more obvious to form a nested structure but it may also be that my eyes are trained to see them exactly as such.