While this book aims to be as complete and thorough as possible, some people simply learn and retain information better when it is presented verbally and visually through an in-person presentation. If you are one of those people, you will probably absorb a lot of additional material by attending a workshop or class. In addition, workshops and classes offer more specific material and individualized one-on-one attention that a book cannot provide. Not to mention, you will be following Tantric tradition. Remember, historically, Tantra was passed along through teachings imparted personally from a guru to his student.