I keep seeing people adding artists as work disambiguation comments. However, we removed artist credits from works on the basis that we thought the writer relationships and recording artists were sufficient for capturing artists, so I don't think it makes sense to do that. We don't have anything saying that people shouldn't do it though, so I would like a guideline I can link people to, instead of repeatedly explaining why I think it's not a good idea.
I'm not sure exactly what it should say, but I guess basically something along the lines that the writers and performers normally shouldn't be put in the disambiguation comment.
If people really do want a way to associate a performer with a work, I think we should either bring back artist credits for works or add a new artist-work relationship type (e.g. "original performer"). Either way I don't think it belongs in the disambiguation comment.
https://beta.musicbrainz.org/search?page=13&query=comment%3A%5BA+TO+Z%5D&type=work&limit=25&method=advanced is a query for most works with disambiguation comments. Other than soundtracks (another case where we're just duplicating information...), the majority seem to be artist names.
https://beta.musicbrainz.org/search?page=2&query=comment%3Asong&type=work&limit=25&method=advanced is a query for ones where the disambiguation includes "song", it seems pretty much all of those are artist names.