Jonathan,
This sounds interesting, and demonstrates the variety that exists in making assignments and the grading of them. I have given tests (closed book), then given the same test immediately following (to the astonishments of the students), and the second go-around is open book, open notes, group effort. That second test of course is graded with less weight. That exercise proved to me that students benefited by group study and open access to information. These students learned the tested information in this manner. I have since not done that exercise, but I am convinced of its merit and application to… >>>