That isn't what i'm saying. What I learned was that if a car came in and it showed tire wear and the only thing out of spec was the caster that even though I was taught that caster isn't a tire wearing angle, in fact it very well could be the cause of the tire wear. There is enough range in the specs on some cars that it might not even show up as being out of spec individualy. But when compared to each other it was a problem.