Sam doesn't believe Dean is smart
This story has Sam trying to figure out a riddle or something and he can't, it's quite long and complicated, I think Dean looks over Sam's shoulder and after reading it a few times works out the answer and Sam can't believe it. Does anyone know the story I'm talking about, and if there are any more stories out there about Sam thinking Dean's not as smart as him then finding out he is, please include them in the comments. Thx