We have rules for almost every kind of interaction with the batter, or batter runner and catcher around the plate...On D3K's, on a pitch when the the batter remains a batter and the catcher needs to gather a misplayed ball, on a batted ball when he becomes a batter runner. Ball four should fall into one of these categories, and I don't think it should be arbitrary as to which one. All I'm saying is "there's no rule so it's nothing" doesn't convince me on this play.