There are some aspects of this book that I didn't like as much, but the core of it was so well done and a necessary addition to Freud literature, that I fully recommend this book.
This book is essentially an explanatory story. It goes over Freud's life and academic career, explaining in great detail the origins and failures of both his modus operandi and his theories. I had initially hoped for science studies that actively disproved the theories, but you don't have to get far into the book to realize that history and logic are enough.
Freud and his theories had very specific failings that both explain the appeal, and explain the weaknesses.
Freud was not a good scientist, while at the same time trusted his genius disproportionately. This led him more than once to publish findings that had not actually occurred (curing addiction with cocaine, curing Anna O with talking therapy), because he trusted that even if the immediate evidence was contrary, he believed his own theories were of such value that they needed to be published regardless.
When dealing with patients and comparing his theories to reality, he did not adopt anything close to a scientific approach which would allow him to falsify his theory. Instead, due to how he constructed the theory, anything could be interpreted by it. Instead of bending theories to fit facts, he bent facts to fit theories, and often to the detriment of his own patients.
Freud wanted to "unlock every door with one key". His stubbornness in this regard is what led him to interpret every neurosis as having a sexual origin, and then every psychological difficulty as having a sexual origin. This led him to defend connections that could not exist, rendering his theory all the more crazy.
He had "issues". He jealously protected his theories from any and all criticism, going so far as to ostracize his followers any time they started actually thinking on their own. This is the antithesis of science, which is based on mutual criticism for the sake of refining or eventually discarding poor theories.
He sucked at understanding people. He had them confess their darkest secrets, tied to their sexual desires, and was then surprised when these people formed an attachment to him, and when he did not respond with even the faintest sympathy, they would of course react negatively.
His therapy was no therapy at all, for he tried to dredge up unconscious desires, only to then criticize them, and force patients to repress them consciously. He was a moralist, judging them. He actually had no regard for his patients, considering them only tools with which to build his theories.
He even treated his "friends" poorly, keeping them close only if they agreed with him, always keeping them at a distance to maintain his authority. He would claim that there was no need to demonize categories of people, and yet he used his own diagnostic labels to insult his opponents.
In essence, he was a bad doctor, a bad scientist, a bad person, and a bad theorist. It is too generous to say he is "overrated", he was in fact entirely "misrated".
One of the main points of this book are the fundamental similarities between Freud, psychoanalysis and the judeo-christian religions. They don't explain what Freud was wrong about, so much as why he had so much appeal, how he treated his followers, and how he viewed himself and his theory.
For the first two parts of this book, the prose really flows, its almost like reading a novel (in terms of how it keeps you reading). The last segment, in part because it was completely different to the first, and in part because it was far less informative and supposedly more "thought provoking", I found it largely unnecessary, and it lengthens an already large book far too much. It barely mentions Freud and his theories and all, and its essentially about the value of mind research, with all of its dangers and pitfalls.
I really think a smaller version of this book should become mandatory reading for all psychology students. I also think it is a good text to recommend to people who value Freud a little too much (without putting your relationship with them at risk).
edit: I tried having a Freud follower read it, but it didn't work :(