It seems that this would be a userful feature. However, Tim, you do point out the problem with questions that "might" be picked.
So there seems to be two types of questions that can be asked:
1) Where has this question been used?
2) Where might this question be used?
Maybe both of these questions can be part of the question's "edit" menu (see graphic.)
For #1, my guess is that the report would show the course and the quiz name (within the course.)
For #2, this (to me) seems harder. The report could be identical to #1. But finding the "where used" would use the question's category instead of the question's id to take care of questions that might be randomly selected.
I think that I would be satisfied with Course and Quiz, but some people might want to take this to the "student" level, as in "Which students have had this question."
Whoever writes the code might try to satisfy #2, and then add to the report a column for "Used" if the question has been used by any student. This is another way of handling both #1 and #2. I think in the Edit menu the addition of a "Where used?" link would be sufficient.
