The most interesting chapter to me is the last one, where he argues that these failures are not evidence of a crappy system, but results of the way our memory functions, which It generally does remarkably well. A large degree of forgetting is actually necessary, so that we can hold onto the gist of what we learn, rather than being swamped by irrelevant details. This can result in bias, stereotyping, euphoric recall, intrusive recurrence of trauma , etc., but there is no way our brains as they are can have perfect recall, though there are useful guidelines one can use when trying to assess memory as accurately as possible. Police, for instance, have changed the types of questions they ask in order to ascertain what witnesses remember, and as a result, get much better information.
It's not overly technical. I did occasionally have to reread a passage to get a handle on it, but only because the material he was handling is not always simple. I found his writing style direct & clear. I'll probably keep this book for reference.