Thanks for the elaboration, I now understand that you are referring to the Music Explorer tab.
i have a little sorting problem but this only happens with one artist.
I gotta say, that is strange bob. But you're right in that something weird is going on specific to this artist syntax.
In the Music Explorer, albums tracks are only placed in the "Appears On" section when the <artist> is different from <album artist>.
I always thought MusicBee is making an
<album artist> is equal to <artist> comparison, but it seems to be more of
<album artist> contains <artist>.
Not sure if that is intended or the ideal comparison, but either way, you'll have to wait for Steven (MusicBee's developer)
or someone else to confirm my suspicion above and/or offer other insights.