Light Bulbs Redux: Lancastrians, Yorkists, and the Rest of the Gang

What can I say? It's as if a light bulb went off in my head last night. Here are some historical light bulb jokes:

How many Lancastrians does it take to change a light bulb? Seventeen--twelve to take shifts changing the light bulb, two to hide the Keeper of the Light Bulbs from the wrath of Queen Margaret, two to conceal the queen's Beaufort lover of the moment in the wardrobe while the light bulb is being changed, and one to reassure King Henry that the new light bulb will not be used to help...