This is indeed a nice trick. There are ways without XSLT, it might even be less painful.

Here is another point of view on the XSLT situation in the WHATWG. Clearly the process needs to be made clearer. I'm not necessarily convinced by everything which is brought forth in this piece, still nice to have different point of views on it.

Or why the XML roots of the web are important to keep in shape. I'm not necessarily in love with how verbose XML is, but it's been a great enabler for interoperability. That's indeed the latter reason which pushed Google to try to get rid of it as much as possible.