I love how every fanfic seems to have a different version of the adjective/expletive Ed will commonly use when addressing someone in exasperation:
“Damn it, Mustang!”
He says “Jeez, Al” because ‘Jeez’ is an alteration of Jesus. And since Jesus is the son of God, it represents his and Al’s attempt at playing God. Namely, trying to bring their mother back to life.
He says “Damn it, Mustang!” because Mustang is the man who opened the door for him to become a State Alchemist. Many civilians see the State Alchemists as having sold their souls to the Military, and are thus damned.
And he says “Fuck, Winry” because he wants to…
Well, remove the comma.