Right, because players that play their natural positions never get injured there. I'm not defending the move to put Vaugh in RF, but I don't think this is a valid argument for it.
Vaughn is going to be just fine in right field, honestly. But there's much more of an injury risk for him in the outfield than at 1B or DH, and his bat is more important than anything. That's the main reason I don't want him playing RF
The only thing you'd really have in baseball that might be considered a specialist is the backup pinch-runner. Used to be left-handed specialists before the 3-batter minimum rule.