Hi Scott:
I think textbooks serve both as a resource for the course and a reference for further study, perhaps at a later time when the student understands the topic or subject better. There is no rule (usually) that say's every word in every chapter has to be used. You're right, we have to prioitize and use the textbook as a tool, and a that tool doesn't have to dominate the project (class lessons).
Regards, Barry
