And in his defense, someone who has not used BeautifulSoup might not realize how robust it is. I was deeply impressed with it when I used it for a scraping project - it's really good at handling tag soup and giving you powerful access to the parse tree. I would not have expected one tool to perform well in both those areas.

ESR probably just made some assumptions about the capabilities of available parsing options that would be correct but for a few exceptional tools. Let's fault him for not checking his assumptions rather than name-calling about poor programming.