As an end-user, AMP breaks 'back' on my iPhone when I navigate to articles (including those from Condé Nast) linked to from Google News. I have to scroll up and use Google's custom back button; using left/right swipe gestures or the browser's back causes problems. Sometimes it's so bad that when I reload the page, I get some weird error from Google about how I got there, which is doubly weird because it's their fault I'm there because they're intentionally wrapping/breaking standard functionality.