I have suffered badly in the past and will probably always continue to do so. It's an ongoing life long illness. I personally haven't learnt anything new, however things I knew previously have been cemented further.
Without food your body starts to shut down, and during this time I was in a couple of near-serious car accidents because my brain began to stop functioning properly. All the things you know when you 'recover' from an ED are things you have known since a child - for me anyway, it's just I didn't really understand the consequences until I stopped eating.
My eating disorder wasn't because of appearance or body dysmorphia, more to do with the control aspects that it gave me, so I guess i may have learned how to control other aspects of my life in a less harmful way.