I generally agree with that point but this feels a bit different.
I'd have kept Moult as he'd get his big contract at the end of the season and we could do with his goals but with Carson it's either move to Celtic in the next 24 hours or see out his career with us. Obviously that's not necessarily a bad thing but the guy is 29 and hasn't made any money out of the game, moving will change the rest of his life.