Southern Comfort wrote:Given that choir-only pieces during Communion ought to be discarded
Oh I don't think the documents were quite so draconian - but I know what you mean!
GIRM87. In the dioceses of the England and Wales the options for the Communion
chant are as follows: (1) the antiphon from the Graduale Romanum either with
or without the psalm; (2) the antiphon with the psalm from the Graduale
Simplex; (3) a song from another collection of psalms and antiphons, approved
by the Bishops’ Conference of England and Wales. It is sung either by the choir
alone or by the choir or cantor with the people.
If there is no singing, however, the Communion antiphon found in the Missal
may be recited either by the faithful, or by some of them, or by a lector.
Otherwise the priest himself says it after he has received Communion and before
he distributes Communion to the faithful.
Communion Song - CTM213 The Communion of priest and people is helpfully
accompanied by prayerful congregational song. This singing is
meant to express the communicants’ union in spirit by means of
the unity of their voices, to give evidence of joy of heart, and
to highlight more the “communitarian” nature of the
Communion procession The Roman Rite provides an antiphon
to be sung at this point. The antiphon may be replaced by a
psalm or suitable liturgical song. The text and the music should
be suited to the mystery being celebrated, the part of the Mass,
the liturgical season or the day.312 The singing continues for as
long as the faithful are receiving the Sacrament. If, however,
there is to be a hymn after Communion, the Communion chant
should be ended at the right time.313
• The communion song begins immediately after the common
recital of L o rd, I am not worthy and normally should
continue until all the assembly have received Communion.
• So as not to encumber the assembly with books or
scripts during the procession, the song may be led by
cantor or choir and include a repeated response or
refrain from the assembly.
• Care must be taken to ensure that cantors and musicians are
also able to receive Communion conveniently.314
• When it is clear that the communion procession is going
to take a long time, thought should be given to extending
the duration of the communion song by way of musical
improvisation, rather than adding additional songs or
allowing part of the communion procession to take
place in silence. However, when necessary a second
communion song or a motet may be sung or instrumental
music played.
• Many traditional Eucharistic hymns were composed for
Benediction of the Most Blessed Sacrament. They concentrate
on adoration rather than on the action of communion and
may not be appropriate as communion songs.
• When there is no music to accompany the procession the
antiphon might be recited by the priest. This should be
done after he has received Communion and before he
distributes Communion to the faithful.