If I am a grader and I decided to hide the grade for one student for an assignment, I can still see it in the Grader report (but the font is gray).
If I (again as a grader) go to the user report for this user I:
- CAN see the assignment
- CAN NOT see any grade, not even gray, in the columns 'Grade', 'Percentage', 'Rank'
- CAN see the grade in the column 'Letter grade' (I enabled it in settings)
As a student I don't see this assignment in the user report at all.
There should be a clear policy, what User report shows if it is viewed by a grader:
1) it shows the same as Grader report but for a particular user
2) it shows the same as what this user would see in his User report
Depending on this policy the hidden grades should be shown or the whole line with module should not be shown at all.
Regarding 'Rank': there should be also a policy whether to include the hidden grades in rank or not. At the moment they are included, so for other students the rank is calculated as if hidden grades were normal grades. But for student whose grade is hidden, rank is not displayed (although exists)
The column 'Average' displays the average only for grades that are not hidden. So for other users it looks strange: "Rank 2/4, Average 30.00 (3)"
So I would suggest that Rank should not include hidden grades