I think this information should appear in the disambiguation for the release group, and not in the title itself. Here are some examples of releases where the phrase is not included in the title even though it appears on the cover:
School of Rock: 39dceead-acc4-438c-830e-2b0174e2d05e
Avenue Q: 29aed286-78f4-4b96-b689-765f46d02e8a
Kinky Boots: e1ba3c76-7b32-40a2-8fbf-56b985518556
Charlie and the Chocolate Factory: c16dfb92-ecea-44fe-8e5e-7dd92c31b552
Mamma Mia!: 89a2d71e-11fc-3247-9375-4a65cd69ed90
Beauty and the Beast: fbc792b3-aee1-4e32-99a0-d715fbbad959
42nd Street: a07118e2-1bef-43e2-8c1c-cb3b669cda34
Fiddler on the Roof: f1640d7b-e320-4a20-bbb4-11e778bccee5
Hello, Dolly!: 26178fec-f08c-431b-bf40-332774137c39
Mary Poppins: d3577544-e7e8-405a-befb-afeda50c9a24
Man of La Mancha: 762a0095-6345-45b4-b7eb-5c2a7ca49b6e
Monty Python’s Spamalot: 59666b97-9c9f-4ba1-9a1b-dd9971d39824
The official MusicBrainz style guidelines point to Allegro as a “correct” example (see the “disambiguation” section). Even though the phrase “Sung by Members of the Original Cast” appears on the cover, it does not appear in the title of the release or the release group. The style guidelines say this is correct, so I think that logic should apply to other releases as well.
221bbs disagrees, and has blocked several of my edits:
“Original Broadway Cast Recording” is an important part of the title. The people who sang in a musical is just as important as the title itself, especially if there are multiple cast recordings. Why would you remove it or not include it if it’s on the release itself?
It seems to me that the official style guidelines disagree. Am I wrong here?