I think Hando311 is asking how you activate the dictionary.

Not why it's in the course.
I have the same question. I have a goal (lofty as it may be) to memorize the entire dictionary. Or at least become good enough at PRing to flip through it a few times and be able to mind probe the definition for any word.

Hando I would say just keep using the system on other books until you get a good grasp of the system. Then when you're an intermediate level PReader, your intuition will tell you how to activate the dictionary.