LOTS of information. Occasionally goofy editing. I am about 3/4 through the book and so far it has scared the heck out of me! No solid "rules to go by" yet but a lot of information on what goes wrong if you stop too deep, stop too shallow, ascend too quickly, ascend too slowly, stay deep too long, don't stay deep LONG ENOUGH, stop at the right depth but ascend too slowly, etc.
Lots of information on lesions in your eyes, brain, spine. Bubbles everywhere. Sudden death caused by cracking your knuckles while ascending. Bladder failure caused by bending your spine too far at your safety stop. It might even be possible to be turned into a face eating zombie if your knuckles crack hoisting your tank by the valve...
If this book is widely read PADI will be besieged by people asking for refunds on their OW cards!