Agreed. The DOM is incredibly slow, and his example is so asinine.

What is the use case for generating 2000 unstyled divs with one line of text? Try making that into a nice slick CSS list, maybe throw an image in each list item, with some title copy and supporting text. Perhaps you throw a bit of text shadow on it to create a nice beveled effect. Oh yeah, that 2000 divs per 200 milliseconds probably just turned into 10. Maybe even less, maybe 1 or 2 on a mobile browser.