Remember "Fall Weather Friends"? And all those events Rainbow Dash cheated at by using her wings? When she first cheated at the long jump, flapping her way past Applejack's hoofprints, I imagined Homestar Runner from the Strongest Man in the World Competition cartoon saying "Did nopony just SEE that?? Twilight? Spike? Giant bee?"
And then later, when Rainbow Dash pulled THIS during the tug-of-war: