Theory states that a man will not have sex with a below average or unattractive woman unless it is possible to obtain a threesome accompanied by a second female of equal physical appearance. Evidence may prove this theory when factoring in alcohol and the fact that a small percentage of males actually have the opportunity to have sex with two women at once.
Billy: Would you nail Megan?
John: No way, she looks like she got punched in the face!
Billy: Me neither, what about Christy?
John: Hell no, shes a rat nasty skank!
Billy: Ya they're gross but I'd nail em both at the same time!
John: Ya dude the 2 chick theory!