In the first Mad Max the term 'Mad' had a double barrelled connotation - in the first instance it was a reflection of the way the world was spiralling into madness as society and civilisation slowly unravelled due to the lack of an governing power; this was shown through Toecutter and his gangs behaviour and actions. in the second instance it was a description of the cold and dark emotional state of the movies title character after the murder of his wife and son.
But with each subsequent movie, only the madness of the world around Max grew, Max's rage and hatred seemed to subside into mourning, with Max showing little if any emotion. It is for this reason alone that I am hoping that Immortan Joe is revealed to be the Toecutter, as it would be a reason for Max's madness to return; having unknowingly let one of his familys killers survive.
