I agree. So tell me what difference it makes what correction factor you use? All it does is change the corrected number.
I’ve had swings from about a 5% correction to over 13% correction. I don’t know that the numbers are more or less accurate at either end of the range but again it doesn’t matter which CF you use the only time those numbers will be correct in the car is when the weather conditions match the CF.
There isn’t one CF that’s better or more correct. Using a CF other than STP doesn’t change anything other than the end number.