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I believe most of the tricks about the influence the author mentions in the book are quite well-known by most people. This book is filled with stories and examples that support the POV of the writer, of which some are actually not that strong. It could be 80% thinner and we can still get all the ideas the author is talking about.
Imagine a long, narrow, trench that goes on for a hundred miles in a straight line. It's just wide enough for you to walk in and filled with thick, dark mud that comes up to your thighs. Scattered intermittently along the base of this trench are small little scatterings of valuable gems. The only way to find them is to feel the sharp edges under your feet as you trudge along.
You could get out, and race ahead a few miles. After all, you've got a list that gives you a rough idea of where the next scattering of slightly different gems can be found. But there's a good chance you might miss some small treasure if you do.
That's what this book is. At best, 50 pages worth of truly useful information scattered and buried throughout 500+ pages of useless, exhausting muck. There is really great stuff in here, but reading to find it feels a bit like a burden... or a chore.
The author claims this book is written in "a nonacademic, conversational style". If you want to make the argument the author succeeded, you'll still need to be prepared for the most boring conversation of your life. One which you were forced to listen to for an hour, but only spend 5 minutes summarizing for your friends (if you're a good friend).