Rorate Caeli

Questions for our readers: on rubrics, customs and hybrid Masses

Yesterday I watched the webcast of one of the handful of diocesan / "Summorum Pontificum" TLM's in Mexico. The readings (including the Gospel), the "Orate Fratres" and the "Ecce Agnus Dei" were said, not in Latin, but in Spanish only. The Gloria and Credo were sung by the celebrant himself in alternation with the congregation. The Secret and the first part of the Canon (until the Consecration) were said aloud, too loud to have merely been the celebrant's "inaudible" voice being picked up by a microphone. Finally, Spanish hymns were sung during this Missa Cantata (vernacular hymns are supposed to be allowed only for Low Mass) and the priest himself led the faithful in a Spanish-language devotional exercise in honor of Saint Joseph, after the communion rites and before singing the post-communion (in Latin). [I'm aware of the "Prone" and of vernacular devotions that were prayed between the Gospel and the Creed, but not in any other part of the Mass.]

I advocate strict fidelity to the rubrics, in the spirit of reverence for liturgical tradition. At the same time I'm aware that in the years leading up to Vatican II some indults (for particular countries) were handed down by the Congregation for Rites in favor of the vernacular, while many other countries had their own long-standing customs which may or may not have been consonant with the rubrics. (Regarding the vernacular: Poland, for instance, received an indult on July 7, 1961 allowing the Gloria, Credo, Sanctus and Agnus Dei to be sung in Polish at a Sung Mass, and the Deutsche Singmesse and Betsingmesse need no introduction.) Here are my questions:

1) Were any (or even all) of the peculiarities that I described above, considered as legitimate customs in the liturgy (in Mexico or anywhere else) prior to Vatican II? I'd be very surprised to learn that saying the Secret and part of the Canon audibly was ever allowed anywhere.

2) Does anyone here have any idea how widespread the singing of vernacular hymns at a Sung Mass has been, either in the era prior to 1964, or in TLM's post-1984?

Feel free as well to post in the combox on "hybrid Masses" and peculiar customs (whether legitimate or not) that have entered into TLM celebrations anywhere in the world.

[Moderator NOTE: Do NOT feel free to criticize at will; this is NOT A DEBATE, but a descriptive post, for comments that include descriptions of events or knowledge of exceptions, but not the unbridled criticism of a regular forum. Thank you.]