Thought experiment [on XML]

The point of his argument is that you forgot about pesky humans, and real life software - where strict parsing means a computer that's much less useful.

(In his particular example, which is just an example and not the whole point, you could parse trackbacks strictly, and still give people browsers that just work. And strictly parsed but poorly filtered third party HTML will give you XSS attacks, too. And his example happened to be buggy filtering of charsets, and not specifically poor parsing. So I don't really see the objection.)