Hypothetical. You wake up early to do some yoga. As you make your way back to your bedroom, you notice the wife is looking solid and willing. For the record your glasses are off and vision is questionable. So.....you start giving her the M2 special. I mean just letting her have it. You've been at it for what seems like hours (37 seconds) and decide to put your glasses on and realize it's your wife's twin. Now, is it cheating if you finish up? For the record you're already half way done in this hypothetical.