This is one of those cases where science doesn’t care what your opinion is.
The implementation is here:
I believe MovieFan.Plex has incorporated my SQL statements into the database tool.
If you put a home move in your plex library, using no matcher, but editing the title and poster in the plex web ui - you will lose your edits when you move no matter how carefully you follow the FAQ. Or if you upload a custom poster for something that matched using imdb, you will also lose that poster. I think a better FAQ would simply tell people that they will lose manual edits, and that the move procedure is meant to pick up properly named files that can be matched by default matchers.
Joseph Elwell.