We have had reports in our institution of issues where excluding individual grades for individual students in a course does not exclude those grades from the calculated class average for the grade item while it does indeed work correctly for the course total. If this is intentional, it may be best to clarify the functionality in the name and the tool-tip, as this not working for averages is not immediately obvious to users. I have attached screenshots of the setting in question, as well as the gradebook example where the average should be 100 if the exclusion had worked correctly.