I learned that if you're making a movie set in the 1980's, you can just put a caption at the beginning that says '1983' and make no further effort to be authentic.
I learned that, according to the filmmakers, fashionable people in the 1980's dressed in whatever random items of clothings they had around the house. Fishing waders, pinwheel hats, frilly pirate shirts, whatever. Case in point, Mariah's Tour de France outfit or that Andy Dick guy's suitjacket with leather sleeves.
I also learned that I have no idea how I was supposed to feel about Dice by the end of the movie. Was he a good guy? A bad guy? A whiny douche bag? Am I supposed to be sad that a perpetually stoned-looking Terrance Howard shoots him?
Oh yeah, I also learned that Maryland, a state with a population of over five million, looks a lot like rural Minnesota. Thanks movie!