Talk:List of ponies/Unicorn ponies/@comment-76.9.78.163-20120410065224/@comment-4354388-20120419051753

Holly Dash's creator is actually an animator in the show. This link (which is already in this list) explains that the animator herself was nicknamed Holly Dash and drew herself as a G3 pony with the same name. When MLP:FiM came around, she re-designed the Holly Dash pony in G4 style, and since she was an animator of that particular show at that particular point, she took her chance and put her pony into the show, colourful hair, strawberry cutie mark and all.

She invented her, she drew her, she named her Holly Dash, she animated her, she put her into the episode.

So in fact, she had all control over the pony in the show, and pretty much only she had any control. The only reason why the name "Holly Dash" shouldn't count as official is because this name is never said in the show.