Having googled, I yet come up empty, but I did find this blog post with a little anecdote on the subject (and with a little reassurance in the combox, as well -- I am not alone in dealing with my alternately feeble and obstreperously ill-behaved recall of persons, places and pithily presented pensees.)
The phrase 'noble simplicity' is often quoted by those who love the Pauline reforms... I remember many years ago when I was a seminarian visiting [another priest], himself then just newly ordained, .... there was an Italian Salesian staying there, and he commented to me:I wonder if instead of "simplicity" of form, we would not do better to say "integrity."You Anglo-Saxons misunderstand this word 'simplicity'. In its latinate context it does not mean 'plain' or 'sober', but rather 'unified', 'harmonious'. So plain vestments in a plain church building are 'simple'. Baroque vestments in a baroque church are 'simple'.
Not being Italian, (or German.... there was some disagreement on the point as the thread progressed,) though hardly Anglo-Saxon either, (my Polish/Norman/Irish/African could generate enough power to light up St Peter's with their spinning, if such a calumny reached their ears,) I need to take this on faith, but it makes sense to me.
And embracing such a definition would clean up a a surprising amount of the mess we are in liturgically.
I myself am a reluctant practitioner of the "blended" liturgy, which is about as far from integrity of form, and "noble simplicity" as can be imagined.
A hodgepodge pleases no one.
The average liturgy is to that ideal liturgy for which we should be striving, as a camel is to a horse.
In fact the constant careening from speech to song is, if you think about it this way, perhaps even more than the mulligan stew of musical styles, the greatest offense against noble simplicity, the largest problem that must be dealt with.
If any of my 2.3 regular readers is more conversant in romanita, I would love to hear from you on this concept of Noble Simplicity.