I currently have my child enrolled in RDI, have taken the More Than Words program, and employed Floortime techniques to interact with my ASD child. So I was really hoping that this book would provide me with more ideas on play based or relationship based therapies. I was really disappointed that this book was more of a theoretical view of autism and how they conducted their study. In fact, the book states that the kids in the study had to meet a certain set of skills before their techniques could be employed. You really can't use their techniques on every child in the autism spectrum (their website states it is targeted for ages 14mos - 3 yrs). Their study even includes a child who can already imitate at 18 months. Are their techniques more for higher functioning ASD children? It kind of makes me wonder.
Now about their techniques, it's just about alternating sessions of ABA and play/social based interactions with the parents (sounds like Floortime or Son Rise to me). They advocate 20 hours of clinical therapy and 5 hours of parent therapy a week. They admit that parents have to be trained by their clinicians, so it's difficult to even use their techniques based upon what's written in the book. This a book for professionals and those who are enrolled in the ESDM program and not the everyday parent.
If you want to communicate and interact with your ASD child, then stick to books like More Than Words: Helping Parents Promote Communication and Social Skills in Children with Autism Spectrum Disorder and Engaging Autism: Using the Floortime Approach to Help Children Relate, Communicate, and Think (Merloyd Lawrence Book). If fact, Greenspan has FREE Webinars and papers that actually tell and teach you how to interact with your ASD child. The Son Rise program also provides free web videos on various ways of engaging with your ASD child (you can find them on various ASD websites).
So if you do RDI, Miller Method, Floortime, Son Rise, or More Than Words, skip this book. In my opinion, it's not worth keeping in your collection for references.