Fair enough, but I think we have a different definition when it comes to "cooking settings" since I mostly play all random and try to get creative with my strategies, which makes Deity pretty frustrating usually. All I'm saying is that some games just can not be won on deity, no matter how good you are. It's a thinking man's game and knowledge can only get you so far. So tipping the odds slightly in your favor makes a HUGE difference and it's something which a lot of people do. Like playing on islands (we all know how bad the AI is at naval battles), adjusting the size of the map, playing the right civs, playing against the right civs, reloading a different map, saving and reloading, etc. Also certain strategies or openings are only viable or advisable depending on the circumstances.
I've watched some of the LP'ers mentioned, they are awesome at this game but none of the games they win (and a lot of it comes down to what, where and against whom they are playing) come close to the impossibility of most of the games I managed get myself into.