It's not a religious text or anything (I suspect that the proselytising tone comes from the fact that at the time it was written, it's recommendations were stil

It's not a religious text or anything (I suspect that the proselytising tone comes from the fact that at the time it was written, it's recommendations were still a bit controversial, especially in the kind of organisations likely to have these kinds of codebases). If it's not useful to you, then that's that. The point is, other books written ten years ago by people with deep expertise (rather than a hypey blog post by someone who just discovered some principle five minutes ago) probably will be.