The dinosaur thing also seems to ignore the fact that when polymorphed, you take on all of your new form's stats, including mental. Dinosaurs aren't known for being that smart (they all have an INT of 2). Were I the DM, depending on the situation, I'd probably be having the dinos rolling some kind of check to see if they got bored and wandered off or possibly got confused about who is their ally and who is their enemy.
