Smart phones have been ubiquitous for years, of course – but much more recently, there seems to have been a shift in social norms. For many people, the unwritten rules of sidewalk choreography now include this: If what I’m reading or watching on my phone is sufficiently interesting to me, it’s entirely up to you to get out of my way, just as if I were very frail, or three years old, or blind. Or a lamppost.