It appears that the submitting MusicBrainz Id/Acoustic Id Paris dialog box has an off by one error.
The text I see:
Checking 5,193 Songs
[-----progress bar is full green, this is not text-----]
5194 Songs processed so far
Off By 1 Error Submitting MusicBrainz Id and Acoustic Id Paris
Yes, I also noticed this wrong counter a long time ago.
The heck with it!