Thank you for finding the article at
http://www.ncregister.com/daily-news/us-bishops-seek-intercession-of-st.-michael
According to it:
“In a letter to priests of the Toledo Diocese, Bishop Thomas said he sees the addition of the prayer, which is to be recited after the dismissal of Mass and before the closing hymn …”
In the description of the Chrism Mass in the
Ceremonial of Bishops we have:
“292 …. After the deacon has said,
The Mass in ended, go in peace (or one of the other formulas), the procession to the vesting room (sacristy) is formed.
293 Then the ceserbearer carrying a censer with burning incense leads the procession, and the blessed oils are carried, each by its own minister, immediately after the cross; the choir and the people sing some verses of the hymn
O Redemptor or some other suitable song.
294 In the vesting room (sacristy) the bishop may instruct the presbyters about the reverent use and safe custody of the holy oils.39.”
So in the Mass they make a Renewal of Priestly Promises, including
“Are you resolved to be faithful stewards of the mysteries of God
in the Holy Eucharist and other liturgical rites …”
Then they will fail to follow Canon 846 §1:
“The liturgical books, approved by the competent authority, are to be faithfully followed in the celebration of the sacraments. Accordingly, no one may on a personal initiative add to or omit or alter anything in those books.”
[From The Code of Canon Law: New Revised English Translation (c) 1997 The Canon Law Society Trust, HarperCollins Liturgical, isbn 000599375X. Excerpts from the English translation of
Ceremonial of Bishops © 1989, International Commission on English in the Liturgy Corporation and
The Roman Missal © 2010 ICEL. All rights reserved.]