I've purchased several books on stretching. My flexibility is pretty poor. This book is at the top of the pile. There's not too much science. Just simple instructions as what to do or not to do.
The diagrams are simple and very effective. The shaded parts represent what is being stretched. There's a good bit about not over stretching and why you may cause damage.
The best of the book is the second half, where it lists stretches for every common sport and the time taken to do all the stretches. There's much more than sports stretches though. There's computer desk, everyday, blue-collar, gardening over 60's, TV and kids stretches (and more too).
Overall, if you dont need too much science then this IS the stretching book for you.