The point is that `detect IE` is so easy with conditional comments but can't be used inside of a script. We can't reliably detect IE. I don't want to use the user agent string and parse the version.

We'd need to document something like this http://stackoverflow.com/questions/11846747/using-conditional-comments-with-requirejs-to-load-ie7-8-only-jquery . But I'm not a big fan of this particular solution using a class on the document.