1. If you eat a Christmas cookie fresh out of the oven, it has no calories because everyone knows that the first cookie is the test and thus calorie free.
2. If you drink a diet soda after eating your second cookie, it also has no calories because the diet soda cancels out the cookie calories.
3. If a friend comes over while you're making your Christmas cookies and needs to sample, you must sample with your friend. Because your friend's first cookie is calorie free, (rule #1) yours is also. It would be rude to let your friend sample alone and, being the friend that you are, that makes your cookie calorie free.
4. Any cookie calories consumed while walking around will fall to your feet and eventually fall off as you move. This is due to gravity and the density of the caloric mass.