I wanted a guide that focused on the one thing all web developers have in common - the page construction process in the browser. We all use different servers, languages, etc.

HTTP2 will absolutely change a lot of how this works, you're right. I chose not to cover it as it won't be a real option for most developers until nginx supports it (still in alpha). The skills I'm teaching in the article re: the Timeline can still be applied when HTTP2 gains mass adoption, so you can test for yourself whether or not the recommendations in the article still make sense.