Sometimes my ideas are just so silly.
So I got to thinking, Derpy has unfocused eyes, Perry has unfocused eyes. And we know for Perry it's simply part of his cover as mindless domestic pet when in reality he is a suave personification of dynamic fury. So what if Derpy was an agent of the OWCA as well? Dun, dun, dun!!!
EDIT: There is now fanfic based off the idea of Derpy as Agent D! The Derp File
Many thanks to
for the fanfic!