I remember years ago complaining to someone that the manager of a project whose code I needed kept refusing to fix the showstopping bugs in it. His answer was "go over his head to his manager. No more Mr Nice Guy."
I thought it over and he was right: I'd tried being reasonable for as long as I could and this guy was preventing me from doing my job properly. I spoke to his manager (who I had a great relationship with BTW) and the problem was fixed literally within minutes.
Since then I've taken that approach to heart: either work with me or get the hell out of my way because I won't be held back.
The author isn't recommending anybody to be a jerk, but his admonitions to being more forthright, up-front, and a bit less scheming will help people find balance. And in consequence actually treating people with respect rather than project a somewhat false "nice-guy" facade.