...Can you imagine the BS writing that would have come from negotiating peace between bloodsvcking monsters and the adrenaline monkeys that want to kill them?
I look at it the same I look at Dragons. Not all dragons willing followed Alduin, and if you could use Speech to recruit allies, incite a coup, and take over, you could convince your opponent that you guys don't necessarily have to be enemies.
Edit: I can't believe your name is censored when I quote you, "He-LadyoftheEveneing-mains."