Q: Is it appropriate to use the Litany of the Saints at all in the Mass of this Sunday’s Solemnity of All Saints ?
A: It could be done, but it’s not the best idea.
The GIRM gives considerable flexibility for choosing music at the entrance and communion at Mass, and it gives even less advice about music for the preparation of the gifts or the recession. So, a Litany of the Saints is not outside the limits of what’s allowed.
However, its liturgical usage is usually tied to something in particular for which we are asking the intercession of the saints: the baptism of adults (or of children now in the US); the ordination of a deacon, priest or bishop; the dedication of a church and altar; and the consecration of virgins, for example. The litany usually concludes with petitions particular to the event at hand.
All Saints’ Day is a celebration of the saints, but not an appeal to them. On any saints’ days–take Simon and Jude for example—the presidential prayers are addressed to God, though they mention these two apostles. We do not pray to those apostles at Mass on their solemnity. Similarly, the missal never invites a litany to all the saints on November 1. Could be done, but it doesn’t quite express the proper usage of the litany or of the music at Mass.