Also keep in mind that Caruso was only chosen to be the underboss, because he headed a large group of non Castelemarasse in that family, it was to keep the family unified. Once Maranzano was killed he knew there was no way he would have taken over and he knew it...Bonanno was the defacto underboss in terms of power. Reading Bonanno's book he mentions several killings in the war, and with his ego they may have been his, and by stressing how imprtant they were he was taking credit "between the lines" so to speak.