Possible? delete/edit unused genre tags stored by auto-complete
Is there any way to edit the stored ITunes Auto-Complete stash of genre tags? I can -- and do -- clean up the tags I myself want to use, but I have no way to access all those useless, unwanted tags stored by auto-complete. Auto-complete is very useful for entering Info in iTunes but it can be quite the hindrance too. I'm constantly have to do workaround edits to force correction of an auto-complete insistence; and in the Genre dropdown menu, I have to wade through tons of unused, unwanted tags to reach the one I prefer to use.
My third party programs which have auto complete usually ALSO provide me the means to edit and delete such tags. I sure would like to be able to do this in iTunes. What a mess it is.
If there is a way, but involves Terminal, I would appreciate very detailed instructions. The only time I venture into Terminal is when someone kindly holds my hand :-)) and even then, I'm nervous until the deed is done. That I'd consider Terminal shows my desperation to be free of the iTunes autocomplete tyranny.
Lion 10.7.3, iTunes 10.6