Joe, at the time of Vatican II I absolutely endorsed the idea of using the "vernacular" rather than Latin, for the obvious reasons you already stated. People should be able to understand what they hear, sing, and/or recite.

I just think that the music suffered -- the old stuff was really grand and impressive. Everyone knew what the "Gloria" and the "Credo" were saying, and if not, could read along in English in their missals, so singing them in Latin didn't much hurt anyone's understanding.