I feel like you're dismissing an interesting article for the sake of an amusing one liner, and that's pretty much the antithesis of HN.
It is a nicely-written and illustrated article, but it describes a problem that hasn't been considered 'interesting' for decades and can, in any case, be tackled with a caching scheme. Why would they need to run the same intersection logic over and over, when there's only a finite number of glyphs to render in any given document?