What a great post by Valve’s Michael Abrash. The content is interesting: a brisk summary of the technical challenges that still need to be tackled if goggle-style virtual reality or augmented reality are going to work and be compelling. So is the style: it reads like an internal memo—a really good ones. It’s not dumbed-down, not smoothed over for public consumption. There is serious study and rigorous thinking on display here. I wish more organizations deigned to share this kind of writing with the public.