Thank you for sharing this Mr. XYZ. I have been planning a tailwind team and it is helpful to know that Whimsicott is not ideal on it (I have 3 different whimsicotts for different teams, so I've grown addicted to him). Your post also reminded me that as a Gen IV move tutor move, it's available to a lot of other pokemon, like the Fake Out-immune Dragonite and Crobat.
441 D/Cs and counting, baby!
*Contrary to popular belief, this is not a compendium of people who disconnect on Wi-Fi. See: Seinfeld, "The Comeback."