You have that right. The fact is, however, that no one is truley a relativist unless they are totally irrational. Relativism stops when you drive your car to an intersection and see a truck coming down the road. You know that the truck can't be there and not be there at the same time. All of the sudden you get objective in your approach to reality.
People are selective relativist.
One important aspect of your book is its discussion of the various elements that work against the Christian goal of spiritual maturity. I run into people all the time that don't want to be bothered with a serious study of theology. And what they mean by that is that just as a child has no maturity of understanding, so the Christian is not supposed to seek a mature understanding of the content of his or her faith. In regard to evil be infants, but in your thinking be adults. That is, we are not supposed to be sophisticated in our criminality, but we are called specifically to be mature in our understanding.