Consider the following scenario:
User-1 wants to tag an album. He looks up the disc ID and discovers that user-2 has already entered a release. He checks the provided information and tags his songs (which now have a
Some time later, user-2 adds additional information (e.g. scans of the booklet). As it turns out, there are multiple versions of the release, let’s say one with a red booklet and the other one with a blue booklet. User-1 happens to have the blue version and user-2 has uploaded scans of the red version.
Now, even though user-1 carefully checked the available information at the time of tagging, the
MUSICBRAINZ_ALBUMID does not point to the correct release anymore, simply because user-2 has added additional information.
According to Alternate CD matrix/runout inscriptions: enough for a new release?, even minute details like the mould SID code could potentially be entered as separate releases. In other words, the number of “release splits” depends on the amount of research done. There is always the possibility that some (otherwise identical) limited run from a remote pressing plant is discovered that gets its own release. So, if a user wants his metadata to be correct, he has to periodically check whether the release still matches his version.
An alternative approach, that I would like to hear your opinion on, would be to assign UIDs not to releases but to “features” of release groups (e.g. bar code, catalog number, number of pages in the booklet, matrix runout etc.) and to write that information into tags. That way, once the user has verified a feature, it will never go stale.
Another advantage of this approach would be that the user can be notified about new features of a release group when he does a metadata update: “Hey, since your last update, we discovered that there is a huge mark-up for releases with mastering SID codes that end with a ‘2’. We have thus decided to add a feature ‘Mastering SID code’. You might want to check this.” The user can then decide to either check this or ignore it. In both cases, the existing tags are still valid.
And if researchers want to give a name (aka release) to a specific set of feature values (barcode A, 6-page booklet etc.), they could still do this, although it would be clear from the start that such a classification is subject to change at any time. The important distinction, however, would be that releases would be inferred from features and not the other way around.
Please let me know what you think!