Suggested rewrite: Hey Evan, We're mighty sorry, but we understand. If things don't work out at yahoo! as planned we want you to know the door is always open to return, after all we hate to see you go. Please tell the rest of your team that you go with our blessing and that we look forward to seeing you do great things in the future. We all know if there is one thing they need over there it is quality people. Since w…
That's good. It reminds me of TheDailyWTF's piece on a "culture of quitting": http://thedailywtf.com/articles/up-or-out-solving-the-it-tur... It would be ideal if an employee parting ways didn't seem like a betrayal or bad break-up.
If you fire the wrong person like that/send off emails like that it could easily lead to a mass walk-out by sympathizers, so it is not only 'nice' to be nice, it also makes good business sense.
Who knows when and how you run in to each other again.