Actually, Liturgiam Authenticam covers everything that is used in the liturgy, including song. If that were not the case, the CDWDS would not have had to send reminders to the publishing houses regarding the matter. Furthermore, LA also called for national episcopal conferences to revise their music and have a directory of songs. That is what Sing to the Lord was supposed to have been.
It’s not that the CDWDS said “what we really meant was”; rather, they clearly stated what it meant, the publshing houses, as I see it, simply ignored it. Furthemore, had they read the document, they would not have continued to include service music that is not faithful to the official texts of the Church.
I stand by the statements that I have made.