Second coming of Adelman and Petrie? The two-headed GM? Yea right, but a this point I can no longer be surprised by any change of feelings Octopus man has. Who knows, he's got the pocketbook to make just about anyone try a new role.
What makes you think Petrie wants to coach? He's been a GM for many years, and he's quite good at it. The only arrangement that makes sense is Petrie as GM and Adelman as coach.