I think that this book can be interesting for those who are curious about homosexuality, but the book is subject to a ton of assumptions that make it necessary to keep your wits about you as you read.
If you're reading it for yourself or because of someone else, be sure to read a copy of "Stranger at the Gate" by Mel White as well: if you really want information on all sides of the question, White's book is an important component to keep in mind.
Like many people, I have heard press reports and read longer studies about the genetic factor in homosexuality. No one has found a "gay gene" per se--but keep in mind that there are very few human characteristics that have *one* gene associated with them. Even something as simple-seeming as eye color is determined by at least ten different genes. Thus, while no published study has actually identified a "gay gene," *all* the studies point to a strong genetic factor. Cohen and pro-Cohen reviewers of this book make claims like "researchers have shyed away from a genetic factor": this is meant to confuse you. It's true that researchers shy away from a *single* "gay gene," but no scientific researcher looking at evidence out there would say that there no genetic component. I have to say that Cohen's skewed presentation of the facts on this issue is disturbing and makes me wonder why he's trying to hide obvious and readily accessible information.
Cohen's counterexplanations for the origins of homosexuality, explaining why people are gay, are even more poorly supported by scientific research out there. Again, he presents the information in such a way as to confuse the reader--it would have been more honest to admit that his anecdotes and explanations lack the same rigorous testing that other more widely accepted explanations do.
I have been a Christian counselor for over fifteen years. I read this book hopeful it would provide insights, but I have been extremely disappointed in the skewed nature and evasive tactics Cohen uses to "support" his points. This is not as much a guide to therapy or counseling as it is a personal biography of Cohen's experience--which by all accounts has been *highly* unusual. His guidelines for the self-therapy he proposes will not work for the vast majority of people (if not all people): and that's the voice of experience. His assumptions are in many cases faulty.
Cohen is tackling a controversial subject, indeed, but he has been less courageous than evasive. His appearances in interviews on TV, etc., indicate to me that he has ulterior motives in publicizing this book (money? notariety?).
His faulty reasoning, evasive content, and dishonest presentation about the status of scientific research on homosexuality all have lead me to the conslusion that this book is "quacky." My final recommendation: not worth reading.