Sally's moveset is a product of her bipolar personality, and is meant pretty much to make battling her as irritating an experience as possible. This attitude kicked into high gear with the Water Pulse/Shock Wave combo she learned in her sophomore year, then got worse when she discovered the versatility of Natural Gift. Sally's senior moves were chosen specifically to annoy and harass her opponents, and not surprisingly they work quite well in that regard.

ExtremeSpeed is something she knew before coming to the PCA, though exactly how she learned that move is something of a mystery (and she certainly isn't about to say). As for her Pickup ability, let's just say you probably shouldn't leave any pocket-sized valuables unattended around her.