I’m the culprit of the edit @tigerman325 just linked.
I am of the opinion that part names should not be part of the title. Simply put, those part names are not part of the title of the song.
The Style / Titles guide offers no, ahem, guidance on what should be done here:
Is it ETI? I don’t think so. While not part of the main title, it doesn’t not serve to distinguish it from different releases or tracks:
Additional information on a release or track name that is not part of its main title, but intended to distinguish it from different releases or tracks with the same main title (such as version/remix names or live recording info), should be entered in parentheses after the main title.
Is it a Subtitle? I don’t think so. The examples here pertain to album titles, not track titles:
Use a colon ( to separate any subtitles. If there is an alternative dividing punctuation mark such as the question mark (?) or exclamation point (!), use that mark instead of the colon.
Are they Multiple titles / Splits? I don’t think so. These are part names, not individual release or songs:
When a release is a re-release of two or more other releases, a track includes two or more songs, or a split release has different titles for each artist, the title should be split as " Title 1 / Title 2" (space, slash, space). For otherwise unnamed split releases, use “Artist 1 / Artist 2” as the title.
Let’s take an example of the following song:
- The Ice Bridge
a. Eyes East
b. Race Against Time
c. Interaction
It is clear that “1.” indicates the song title: “The Ice Bridge”. Following the Style Guide, there is no provision suggesting that any further information should be added to this title. While the artwork shows that the are parts within this title that have names, they don’t qualify as Subtitles, ETI or Multiple Titles. Given this, they should be omitted from the track title.
I recognize that we do want to document the part names as part of the release. It is relevant text displayed on the artwork. Other databases like Discogs and Rate Your Music have elegant provisions to include this information within the track listing:
https://www.discogs.com/release/20432176-Yes-The-Quest
https://rateyourmusic.com/release/album/yes/the-quest.p/
Unfortunately, MusicBrainz has no such provision. Barring such a provision, I suggest it is preferable to add this information to the annotation rather than cramming it into the title. Not only is it a bit of a kludge, it’s simply not accurate information. Those part names are names of parts, not the name of the title.