My car isn’t tuned on the ragged edge of blowing up and would probably run fine anywhere between 75% and 90%. The difference in ethanol content between those two won’t throw the AFR off substantially from my experience.
I barely run any more timing then my pump gas map, lol. I wish my engine was built so I could crank the boost and take full advantage of the corn.
However I do agree, knowing the content is VERY useful.