The point being, there’s a limitation associated with the DV window. This comes from the aircraft manufacturer, not the company. Everyone acting like they’ve never heard of such a thing. We weren’t allowed to remove or even open our windows, but we still had to know the limitation. We also had to know unusable fuel in each tank though too. To the OP, just learn what your company tells you to learn. They should give you a packet of limitations and memory items. Then just make your flash cards off of that material.