Kotter argues that many people in the workforce are either cynics or naïve; both believing that failures to get things done are due to incompetence or malice on the part of individuals when, more often than not, some existing organizational relationship is overly stressed by the potential change. Good managers, according to Kotter, will develop a detailed knowledge of the formal and informal power structures throughout an entire organization (and beyond) and act accordingly within those power flows to accomplish tasks and drive change. This is an idealized situation for sure. By definition, it is impossible to fully understand the interdependencies in a complex organization (otherwise, it wouldn't be very complex, would it?). To learn all these complex relationships, Kotter advocates being a receptive follower, a peer mentor, a bastion of technical competence, and a good leader to subordinates. In essence, don't be an uncooperative jerk and do a good job.
On the whole, Kotter's argument is sound but deserves a caution that any attempt to manipulate social relationships in a complex organization will probably fail in that it will not produce the exact desired output. A substantial part of this effort should be grooming your bosses in how to manage perceived failure (or in prepping your backup career for when you bet everything on a flawed idea). Entertaining read because of the anecdotes and vignettes, but short on substance.