Just because somebody a fan, doesn't mean they will know everything, that, and it the episode it self, we learn that different people learn differently, Pinkie learns with music, Fluttershy learns with visuals, Rarity learns, through fashion, I guess, Applejack learns by doing, and Twilight learns by studding the fuck out of it.

Well, it's Dash. What do you think she going to care more about; the exciting part of Wonder Bolts or its history. Also, you can be a fan but still know little on them.