No, I'm not going to write the whole book out, bit by bit. I note that Abebooks has plenty of copies available. But I liked this enough to want to share:
"Our so called Missa Cantata is the compromise of a compromise, a Low Mass, with singing as at High Mass, only justifiable to enhance the dignity of Sunday Mass when a deacon and subdeacon cannot be had. (And the practice of saying a Low Mass while the choir sings bits of things is too dreadful to be described.)"