Worried about rust? NOT, I just don't like it. To me, things look best, rust-free. You're right about not driving it enough. I have 5 cars, so it's not likely I'll drive all of them everyday. Surface rust on the swept area is an unavoidable thing, as far as I know. The cad plated rotors will rust there, once the plating is worn off. I am just trying to keep the non-swept areas of the rotors rust free. Some time ago, I refinished a Ruger-22 cal. pistol(hot tank blueing). The "treated" pistol performed as well as a non-treated one. The blueing didn't affect it safety-wise, it was still all it could be. I don't see the "blueing" as having any effect on the function of the rotors, other than interrupting the rust process. After some "stops" the blueing will be worn away on the swept surfaces. I wouldn't put a protective coating, on the blueing, of the swept surfaces, only the non-swept surfaces. I DO believe in "Safety First", so I wouldn't do anything to compromise the stopping ability, like you said, replacement of a front end is a bigger deal than rust. Thanks for the concern, my eyes are wide open, but hard to see that, by an internet forum. Better to be safe than sorry.