As it turns out, they made a great offer for me to return in 2014, but they don't allow remote work and we're staying in Austin. I have many friends in IE/Edge and wish them all the best.

It is my understanding that the IE team appreciates Eric's post-employment bug reports because his visibility gets them bumped up the priority chain[1]

[1] I asked him and that's what he told me.

I'm not sure going back ever seems like the right move. You aren't necessarily opening yourself up to more opportunity in most cases, returning to a former employer, and as your comment indicates, you may find things have changed in ways you don't like while you were gone.

I've not seen too many cases where people going back has succeeded. It is certainly a different sort of relationship post partum.