Apple and I have a strange relationship. It’s mostly based off of hate… but there’s some respect layered in there as well. Apple is a big fan of breaking standards – especially HTML5 video standards. In respect to Retina displays, Apple built Safari to automatically re-render every image to a maximum size of 1024 x 1024. They also built it to never give out dimensions greater than 1024 x 768 when you query the width and height of the screen.
Needless to say, we had to go with non-Retina images in order to get Safari to work correctly… and I was made a liar. There’s a lot of lessons here and I hope others can learn along with me!