first of all, I think most people would much rather learn a totally new musical setting, instead of one with different words that sneak up on you or are awkward to sing
and secondly, since when did the publishers start caring whether or not they used the right text?
for example, I'm looking at the "Mass of Light" right now, and instead of where it used to (incorrectly) say "Glory to God in the the highest, SING, Glory to God," it now says "Glory to God in the highest, glory to God..."
so...it was ok to add/change words in 1988...I wonder what changed now? :-/
(I suppose I should be *glad* that they have realized the importance of using the correct text, but...I am still skeptical of their motives.)
edit: actually, I'd like to modify a bit of what I said. I'm looking through this booklet, and it seems to me that the infamous "Mass of Creation" (or the Gloria at least, cuz that's as far as I've gotten,) may actually be an improvement on the old version! and the parts that are different are different enough that it's not hard to sing, cuz it's like a new verse!