Leslie,
I suppose anytime we ask students a question we are assessing what they know. With select topics (such as APA or MLA), one might save time if the whole class was familiar with the process but I imagine there would still be a need to review the essential points, perhaps give a handout explaining the nuts and bolts so to speak. I would not want to have my first paper assiggnment due and half the class not follow APA rules.
Barry Westling