Clarify use of [theatre] versus join phrases

The theatre guidelines say to use [theatre] in some cases, but the annotation on that artist contradicts that by saying to use join phrases instead. When a generic ensemble name (e.g., "choir") appears in the middle or end of a track/recording credit, should it be credited to [theatre], or as a join phrase?

(I prefer to avoid crediting pseudo-artists in join phrases, so I think using [theatre] is better than using join phrases in this case.)