apparently, Microsoft believes that most Intranet sites suck at html. Thats the easiest explanation why IE renders every site it considers an intranet site in the compatible mode (its the I suck at rendering mode).
There is one way to fix that, you can tell IE with a special tag in the head area to render the page in a specific (ie modern) IE rendering mode.
But this header only works, if it appears BEFORE the css and js inclusions.
So it would be nice to either have a fake requirement that can add this header, or way to declare that resources should be included at the end of the head section.
I had this problem months ago, I didn't file a bug because apparently, setting this as a http header also did the trick. Now I file it because I was asked for it @EuroPython.