This is a rough start. I finally broke down and started taking notes (something I don't normally do), but it was the only way I could keep things organized.
The book assumes that the reader has read all seven books in the series. Okay, fair enough. If I was not a fan of the books, I would not read this. However, someone who has an interest in spying might pick up this book out of curiosity and essentially be shit out of luck. It does kind of explains certain things...but you really have to have read the HP series to truly understand this.
Not crazy about the fact that the book opens up discussing the fifth book (Harry Potter and the Order of the Phoenix). I guess there's nothing wrong with that per say...but it just seems weird.
At certain passages, noticeably in analysis asides that are scattered throughout the chapters, I kind of was getting a feeling of the authors being slightly condescending
ANALYSIS: Why are Harry's friends refusing to say much in their letters to Harry? They fear that their letters may be intercepted!
Maybe I'm reading too much into it...but yeah, I think the audience is a bit brighter then we're getting credited for.
There are several asides scattered throughout the chapter(s). They are interesting, but a little distracting. I think they are used to break up the chapter into subsections but it kind of breaks up the flow of the narrative as they are right in the middle of the page and although there are lines to "box" in those asides...it's still distracting. I would probably put those in small boxes and off set those boxes from the rest of the text...or I would physically break the chapters up into the subsections with numbers or titles.
Speaking of the asides, one was a reference to a book not related to the HP series, but it fit in with the topic on hand. At first I was interested in the book, but then the aside ended with mentioning that one of the authors was one of the primary researches for the book which made the whole thing sound like a plug instead of a legit reference.
And on a final note on the chapter (for now anyway, I had a few other issues that I'll keep to myself)...I was extremely annoyed by the liberal use of exclamation points. It is one of my personal book pet peeves, so maybe other people will not to bothered, but I get annoyed when a writer abuses the exclamation point.