I've been using this style - with some tweaks - for web apps too. I don't think I have it completely figured out yet, but it's promising so far. You can view the source of http://lofi.limo/ to see how it's working out.
I don't think that's correct. The article is literally talking about how to write HTML, and explaining the benefits of writing it in this style.
Not with that attidude... if you write consistently and with intention, it turns out just fine.
Check out the source for https://try.nodebb.org, for example. Dynamically generated, (mostly) syntactically correct, (mostly) human readable.