I had this done as part of a comprehensive bike fit. I broke my foot playing baseball in highschool and it is rather toed in. My cleat on that side is also toed in to make to make the knee, hip, ankle track in a straight line. It gave a reading of 4.5 degrees of toe in. The thing that I found interesting is that he recommended I install a red cleat on the bad foot and leave the grey one on the other. I know I never would have tried that on my own. Although I never felt I had a problem on that side(previous bike fit) I do feel better. Really simple to do just ride.