I like to think that iceman has a glitch in his system that makes him clinically fucking insane, explaining why he sometimes talks to himself pretending to be comunicating with some sort of general and why he's constantly pretending to be an army soldier
Before the game was released, Iceman's dialogue with Yellow Devil and CWU-01P were switched around by accident. That's why he says "You don't make any sense!" when he was talking to CWU-01P; he was supposed to say that to Yellow Devil, implying that he doesn't understand him. It seems the only one who can understand Yellow Devil is Oilman, who can also somehow speak his language.
ice man acting ike TF2 soldier be like: dr light: what insanity usuing my robots to conquer the world! ice man: if fighting is sure to result in victory then you must fight!