my point is that you can't just say..... richen the engine when it's hotter out.

that does not work except if you are just tuning for temperature and not performance. An aspirated engine- be it two or four stroke is designed to run at a narrow range of air fuel mixture for optimal performance. Tell me how richening your engine when it's hot accomplishes this? It doesn't

For example: a normally aspirated engine (which we have here) needs around 12 or 14:1 air(oxygen)/fuel mixture. If there is less air (oxygen) when it's hot, the engine needs less fuel to run optimally (performance wise). I'm not saying it won't run.... it just won't run optimally.

On an average race day you run rich in the morning when it's cold and leaner in the afternoon when it's hotter. By the time the mains roll around it's time to richen them up again as the sun is setting.

If you don't understand that I can't help you any farther.... it's simple physics