How to read a textbook for distance learning coursework - do I need to work on fact recall, or is understanding enough? There's perhaps a better title for this question, but I can't immediate think of one - suggestions for amendment welcome.

I'd like to clarify the purpose of reading textbooks. It sounds obvious at first, but what I mean is opaque to me.

I'm currently reading a textbook describing ~35 problem-solving and improvement methods, as part of this course. It is densely packed with definitions, ideas, procedures etc. I'm highlighting as I go through and occasionally making notes in the margins.

When I finish reading, I barely remember what I've just read, let alone what I've learned. If I was asked to describe the characteristics of a technique I've just read about, I would struggle to put forward a coherent and strong answer.

Even if I condense my notes and read through them, the problem remains - there are too many 'facts' to learn, remember and regurgitate.

This leads me to ask what the purpose of reading textbooks is. Is it to learn and understand 'facts' and be able to remember them? Or is it to learn and understand? That is, it doesn't necessarily matter if you can't remember, so long as you can understand ideas when you revisit them and can argue them in your work.

For clarity, I'm a distance-learning student with The Open University, so the textbook I'm referring to isn't a traditional textbook, but one that is perhaps closely identified by F'x as a coursework book. These books are used in place of lectures, and so are meant to be read in a linear fashion on a week-by-week basis.
It might helpful to change the question slightly, into 


  What is the purpose of writing a textbook?


Usually a textbook is written to lay out a fairly well codified body of knowledge about a topic. The "well codified" part is important: it's expected that this body of knowledge has some lasting value. The textbook is also written (hopefully) in a way that *teaches this knowledge, as opposed to merely dumping it out. 

To me it sounds like the book you're reading is of the second kind (a dump of facts). Such a textbook is better treated as a reference book, like a dictionary. No one reads a dictionary (unless they're trying to pass the GRE or win a spelling bee :)), but they will refer to it to get the meanings of words. 

Similarly, with a book that describes 35 problem solving methods, maybe reading it cover to cover isn't the best strategy. Rather, you should focus on a few techniques (or even one) and try to understand that well. Then put the book away and revisit it from time to time.

So to answer your question: 


  A textbook can be a collection of facts, but often it's more than
  that: it's a path through the facts that provides a structure with
  which to process the facts. The goal of reading (and learning) is to
  acquire both the facts AND the structure. The facts will be easier to
  remember if you have the structure in place, and the structure makes
  more sense with the facts as examples.