Best post. Even looking at canned food, you can't expect to get the EXACT same number of calories between two cans of chili. These are all estimates....so you know if you eat pretty much the same things, you can still count them as constants.
The only reason for a difference in raw or cooked is that some water and fat will be lost in cooking. OBVIOUSLY if I grill my own red meat, it will have less grease than the same pound of beef at Micky D's