Several months ago, I was working with a driver who felt they had hit a plateau with their performance at Road America. During the session, they said they always had trouble with the first two 90 degree corners. I mentioned offhandedly that the corners were actually a bit over and under 90 degrees. They replied with surprise remarking that they didn’t realize that. This made me think we might have found the root of the problem so I showed them the two images below which are featureless, but accurate representations of the two corners in question. They weren’t able to tell which was which.