I don't think the scorer had a choice on the win. Affeldt was the pitcher of record when the go-ahead run was scored. No spite involved. I was actually surprised when I heard Bum was getting the win.
The only time the scorer has a choice is if the SP is the pitcher if record and he does not go 5. In that sutuation, he CANNOT get the win.
You may be right, but I am far too drunk to look that shit up!