The duality of Kirk Cousins is such that he prepares meticulously in situations leading up to games — with his body, with his film study, you name it — so that he has as much control as possible over the three hours out of 168 spent between the lines every week during the season.
But in those three hours, that control is ceded to the whims and emotions of a game. A seemingly reserved Cousins can get caught up in the joy or frustration of the moment — as we've seen famously in the past whether he is shouting, "You like that!