"The Rules" and Actuosa Participatio

Perhaps the single most mis-understood phrase in all of SC (the document on the Liturgy of VatII) is the phrase "actuosa participatio".

The Latin is best approximated by the English "complete participation," but translators usually render "actuosa" as "active." That translation is barely adequate for the sense of the word "actuosa;" it lends to the "sing, respond, stand, kneel (and in worse cases) mimic the priest" syndromes, with the inevitable result that the Liturgy becomes horizontal rather than vertical.

In any case, here's a parallel observation from an essay by CosmosLiturgy, commenting on Jesus' admonitions of the Pharisees:

So what is Jesus saying to the Pharisees and scribes if he is not telling them stop pushing the rules? Jesus is telling them to change their hearts. His point is that the rules are meant to transform them[...] interiorly through observance of exterior behavior. Both are necessary.

"Change ...hearts." That's the real intent of the controversial phrase. It may or may not mean "sing, respond, stand, kneel..."--but it certainly means "change your heart."