I hate the crew has to deal with retarded fans like this. We had an awesome final and we still have fans bitching over flash being in for a line…I for one hope they add him in more hell have him and twillight get married just to piss them off.

Flash is the Anti-Derpy, all he has to do is be present in order for his presence to have an impact. I honestly don't care much, the only thing that matters to me is that Derpy is cuter and has the uncanny ability to actually be able to blend in with the scenery, a talent that Flash Sentry simply incoming wall of text hasn't shown he can replicate.

However, to the people that actually do care about background characters, it doesn't matter how little of an impact a character has on an episode, all that matters is what the background character represents in the big picture.

When they put Derpy in the episode, it seems to send a light-hearted, playful message of acknowledgement; she was originally a mostly insignificant animation error, but when the fans gave her attention, the animators started adding her in other episodes, which showed that they acknowledged the fans.