The Westminster Cathedral blog has an intriguing post on the how-to-speak-ecclesiastical-Latin battles of the 19th and 20th centuries, concluding:

As Peter Jones notes in ‘The Intelligent person’s Guide to Classics’, the pronunciation of Latin arouses fierce passions. How true. I was requested one evening by a visiting and indignant choir to adopt a more ‘english’ pronunciation for my celebration of Mass, as the music being sung was the very native Byrd and Tallis. Naturally I declined, hinting that I was outraged at the suggestion. In fact, I was very amused.