William,
Pretesting can be whatever and however the instructor wants to structure it. A pretest could be only a couple questions. As to managing the "grading", some instructors might (anonymously) use the pretest as an open class assignment, and all might benefit from what information is obtained. Instructors are creative folks and I'm sure there are ways to work in a few extra minutes - if the instructor sees value in the exercise.
Barry Westling
