Episode 11 of the first season has the girls being trained on princess-etiquette, each lesson ending with a spectacular fail that puts the instructor in the infirmary. Before long the entire room is filled with patients.
Any time the Evil Chancellor tries to use the Prominence. He gains Princess Curls the first time and then gains those along with a dress just like the one the girls wore when they had the Prominence, albeit darker. His Mooks' reactions sell it.