[Byleth will continue to doubt, just like he doubted Claude as well, despite his better acting abilities. But he could see that the conversation risked devolving into a circular argument of some kind, and Byleth lacked the mental energy for it. He decided to concede the point.]

As you say. I can see I can't change your mind... just, be mindful of your own health as well, Dimitri. Don't do anything needlessly reckless.