I think that by writing the article this way around (crossing the road -> refraction of light in glass) the author has rather unfortunately invited the kind of

I think that by writing the article this way around (crossing the road -> refraction of light in glass) the author has rather unfortunately invited the kind of criticisms in this thread, that his "model is flawed" etc. As a contrived scenario to help more intuitively understand refraction, it's nice, and I think that was what he was going for. It's how I read it.