Definitely spoiler stuff here.
Something I've wondered about ever since my second or third playthrough. (At @3500 hours of play, that was quite a long while ago.) Dovahkin manages to trap Oodahviing and extract Alduin's location from him. The location is Skuldafn, high in the mountains. According to Oodahviing, the only way to get there is if a dragon flies the Dovahkin there. The dragon's deal is: I fly you there and then you let me go.
Now, here's my question: Why couldn't Dovahkin use Paarthurnax to fly to Skuldafn and leave Oodahviing a prisoner (where he most likely deserves to be for the rest of eternity)? Paarthurnax has definitely demonstrated that he is very much anti-Alduin, so I can't see any reason why he would decline the request. WHY must it be Oodahviing's way or no way?