I think this nicely captures another mistake by our historian-class and those who borrow from them, namely, simplistic assumptions about cultures and formation. The existence of artifacts that contain ideas says nothing about how those artifacts are received by people. In some cases, they may be consumed uncritically--but the assumption that they are is also mildly disrespectful to the people who buy them. I Kissed Dating Goodbye, for instance, formed a whole generation of evangelicals--to love dating! We read it, argued with it, and went on our way. And this is true of almost every part of "culture." The "formative" power of artifacts is often the inverse of the ideas they actually communicate. Which is why, to tell a full history that aims to show "causes," one has to do much more than the existence of various cultural artifacts; one has to examine how they were received, what difference (if any) they made, and so on. I think this is why the most sensitive and insightful explorations of "evangelicalism" the past twenty years have come from ethnographers, rather than historians.