Hrm, the more I think about this, I think we may be mixing purposes here, since it actually goes both ways.  For multiple choice it maps choice_0 -> 'a table' but for file submissions it maps (the file object) -> 'some_file_path.txt'.  In the file case it's actually replacing the file object with a moniker, and in the multiple choice case it's replacing the moniker with the content.

I need to think about this more.