I thought the original proposal in MDL-46599 was to change it so that a blank in the import file did not cause the grade to be wiped. That makes sense to me.
Then there was a comment that some people might want a way to wipe the grade on import.
Well, you could do that by having a special value, like '-', 'null', or 'No grade' (that last one localised) which when present in the file in place of the grade, would cause the grade to eb wiped.
That seems like a simple solution to the original problem. Am I missing something?
