Yep, you are totally correct, Dave. Most owners don't use enough of the car's suspension and steering to know if there is anything that will rub. A tight autocross slalom will really get the suspension moving through it's range of motion, but very few owners do that with their cars. Mountain roads are another area that puts a lot of articulation into the suspension. I like to find out issues at an autocross since I tend to be close to home. Something else to consider is that if you are running mountain roads with a passenger and a trunk full of items, your static ride height will be less, therefore you may have rubbing that you wouldn't have otherwise. I found that with a full tank of gas, spare tire in the back, Mountune springs, P205/45 17 tires, and two passengers in the back seat, the tires only had about .25" of travel available. That is not good at all! The temporary fix is to remove the spare tire and jack for the summer, don't carry any people, and keep cargo to a very minimum. This spring I am going to address the issue by raising the rear of the car a little. While I never rubbed with the wheel/tire/spring combination, I could clearly see that the amount of suspension travel I have available is severely limited with any weight added to the car. Did it rub? no. Would it rub? yes! It really doesn't take much alterations from stock to start running into issues.
Somewhat related to this is the spring rate and dampers. If you don't take out the springs and check the full range of articulation, but rather just install parts and go for a ride, you may still have issues. With my Focus, I had ran P215/45 17 tires with Progress springs and stock dampers. No issues at all rubbing when autocrossing, track use, or on the street. As the dampers wore out because of the increased spring rate and track/autocross use, I started to get issues where the tires would rub around a corner when hitting a bump with the compressed side of the suspension. The tire size didn't change, the wheels didn't change, the springs didn't change, but the dampers did become worn out and the damping rate dropped. I added a set of Koni yellows and had them at full soft for street use and the rubbing went away. I question a lot of the blanket statements made by people when they talk about what combination of springs, dampers, wheels, and tires work on our cars. The more you change the more potential for issues you have.
