A priest selecting the music for the service would choose one from each group to be sung, and so any setting of a movement could be used in combination with any other.
Because of the wide disparities in style and notation, and because no underlying musical structure (such as a common cantus firmus or parody procedure) has been noted between the mass movements, the Tournai Mass is believed to have been composed independently by several musicians over a period of fifty or more years, and was later compiled by a scribe to be performed as a whole.
The first known mass to have been conceived of and composed as a single unified work is the Messe de Nostre Dame by Guillaume de Machaut, who probably knew the Tournai Mass and may have used it as a model.
[1] The Tournai Mass was first described by Edmund Coussemaker in his 1869 report Une Messe du XIIIe Siecle (his 13th century designation is now considered erroneous).
Anne Walters Robertson has proposed that the mass was not used for the liturgy, but was instead compiled for an "Annunciation drama" to celebrate the Virgin.