I'd hate to be a party pooper here, but the ones most guilty of this are Scions (despoil), APs (with stacked unholies), and liches/mummies (They get a fat health boost).

Joe blow transmuter can stack as much HP as wants, he probably isnt going to be able to double his health pool unless his base health is low to begin with. He'll also end up with garbage saves and no stat buffer against maledicts.