This motu proprio and the work of liturgical reform prior to, at the time of, and after the Second Vatican Council are, to me, an attempt at applying the principle of subsidiarity, from the sphere of Morality (non-ritual worship), to the sphere of Liturgy (ritual worship).

These two theological spheres are 'practical' means of seeking understanding via faith (theology). They needn't be bogged down by the arcane terminologies of imperfect philosophies (e.g. Aristotelianism, Thomism) applied in more systematic means of doing theology.

Understanding and expression are very important in the sphere of Liturgy. If we don't allow Liturgy to develop liturgically, but instead use our imperfect philosophical-theological lexicon to supress expression rather than to guide it, then how can we model the parrhesia of the Church that we read about in the Acts of the Apostles?

I thank God, and Pope Francis, who I believe serves as a channel of God, for this development and I hope that it bears life.