I have seen some of these people cook on a day to day basis and the observation process makes me wonder. When I cook, I strictly follow my mom's recipe or more recently, my wife's directions. If some ingredient should be added in two teaspoons, I follow the law to the dot. While I still think I am ingenious, i like to be safe and cook known good recipes. On the other hand, my mom, my friend, or more recently, my pretty lady cook with abandon. All measurements fly out of the window and they add ingredients as they feel the dish needs. It is scary to see that they seem to throw an unknown amount of spices or salt (yeah, I am an engineer who likes to know the exact measurements). When it is time to eat food, each and every dish tastes great! Their minds apparently work the recipe on the fly. While cooking, their hands sing the tune of their minds.
If you see it once or twice, you think it is a fluke. But if you have been seeing this everyday for 20 years with your mom, 2 years with your friend, or for the last 6 months with da wife, it makes you wonder! Is cooking natural to some people and totally a skill to others?