I don't think that actually addresses the concern presented. "This book is here to guide you" is good; "this book has one INCREDIBLY CRITICAL sentence which is buried 250 pages in" is not. Even if it's in a chapter entitled, "Running the Game," a single ultra-critical sentence changing many if not most instances of a common DMing interaction reflects poorly on that book and its ability to "guide."
If it's important, it's worth saying more than once, or worth at least highlighting. If it's genuinely critical to a large portion of the experience, it absolutely should be said more than once or highlighted. That it isn't is bad organization. Especially when the thing that sentence modifies is actually in a different section altogether.