Manual like textbooks are best handled by seeing each chapter as a book in itself and activate it as such.
Steps photoread the whole manual, postview and activate for 30 minutes (or less since you're really only going to get a good idea of where the chapters are and little else if its a large book.) When you intend to activate one of the chapters photoread the 2 chapters before it the core chapter and 2 following. Lets say this is in case there is information that relates to the core chapter in those other chapters so that if necessary you might get the urge for a closer look at them.
Mind probing questions will relate to your purpose and the subject you are activating. Superread and dip as often as necessary till the chapter has fully gelled for you.
Use superreading and dipping or skittering to activate. That way you see all the words and miss nothing. Even though consciously you heard very few of the words.
BTW your approach on the chemical book has a much more clearly defined purposes for what you what out of that book.
Alex
