It can helpful when you are answering relatively wrong, but not wrong enough. Also, probably when you don’t want to use No Cigar. Or Ignore script, used correctly or not.
Analytics can helpful for adding to blacklists (and additional whitelists), as well as confusion guesser.
I also think of adding additional fields on the review, to send to analytics (such as your idea of synonyms; or you don’t know the nuance, but answered correctly anyways.)
Data might be saved personally in Google Sheets or AirTable; or in a real database, especially when you want to share with others.
Any thought? Any previous attempts / implementations?