Charts and graphs? Come on now, it’s just bbq!!
With cooking there are two extremes in approach, there is feel and analytical. Most folks are somewhere in between but it is interesting to look at the limiting cases.
The cook by feel is the person that can tell doneness very precisely just by pressing on the meat and feeling the response. It takes a lot of experience to be able to do this effectively.
The analytical cook will use instruments like thermometer. I definitely fall on the analytical side. I rely on thermometers and temperature profiles to get the best results.
It has improved the quality and consistency of what I cook. As such, I have a drawer full of very good food thermometers of various sorts.
The best way to cook is the way you enjoy and that produces the desired outcome. It may not be the same approach for me as it is for you. Or you may find that trying a different approach improves your outcome. You won't know until you try.