We are expecting a kid, who hasn't pitched in 4 years, barely above rookie ball, to come up to the majors and pitch better than 99.99999% of the people in this world at the MLB level.
People have said this type of move is unprecedented by Philly, because it was. No GM in baseball would have protected Song, getting upset over this is just pointless. If he ends up being good then that Sux for the Sox but you can't blame this one on them. He probably gets returned. Philly wants to compete and not burn a spot and they likley planned on being able to carry him on the military list this year.