Just get it. Worth every penny.
I wanted to get back into backpacking again but a low back problem was keeping from carrying the weight of my old gear. The information in this book (and Ladigan's book "Lighten Up!") changed my mindset about gear and pack weight entirely.
My friend still carries about 45 lbs of gear for our weekend trips. When he lifted my pack during our last trip he said, "You've gotta be kiddin me!" I just smiled and told him to get the books.
That someone with a 45 pound pack sounds like a graduate of a certain outdoor school. If they had lifted that pack and said "No, this is impossible, I won't allow this into my brain," I would suspect that they're employed at an executive level at that same school.
Just so you know, a 45 pound backpack is considered remarkably light at that school.