The ancient traditional Gregorian Chant must, therefore, in a large measure be restored to the functions of public worship, and the fact must be accepted by all that an ecclesiastical function loses none of its solemnity when accompanied by this music alone.Today, 9th July 2012, I reckon it is a safe bet that in most parishes you will never hear Gregorian Chant. And this is not because they are getting by on a diet of Palestrina and Mozart. (Nor because it isn't Sunday). Tra le Sollecitudini seems to be wasted ink. The Vatican website does not even have an English version.
For those unfamiliar with the terminology of Catholic liturgical books, the parts of the Mass to be sung by the people (or by the choir on behalf of the people) are printed in a book called the Roman Gradual.
Q: Why is it called the Roman Gradual?
A: Because it is being implemented slowly.
(A post on The Chant Café warned me I might have to assert copyright to this joke, which I have been making for a few years now).