Five conciliar documents are brought to bear on GIRM 16, which is essentially the same as the 1975 version of GIRM 1:
16. The celebration of Mass, as the action of Christ and of the People of God arrayed hierarchically, is the center of the whole of Christian life for the Church both universal and local, as well as for each of the faithful individually.[Sacrosanctum Concilium 41; Lumen Gentium 11; Presbyterorum Ordinis 2, 5, 6; Christus Dominus 30; Unitatis Redintegratio 15; Eucharisticum mysterium 3e, 6] For in it is found the high point both of the action by which God sanctifies the world in Christ and of the worship that the human race offers to the Father, adoring him through Christ, the Son of God, in the Holy Spirit.[cf. Sacrosanctum Concilium 10] In it, moreover, during the course of the year, the mysteries of redemption are celebrated so as to be in some way made present.[cf. Sacrosanctum Concilium 102] As to the other sacred actions and all the activities of the Christian life, these are bound up with it, flow from it, and are ordered to it.[Sacrosanctum Concilium 10; cf. Presbyterorum ordinis 5]
The translation of 2011 has indeed been tweaked from the 2002 version, in which the corresponding passages are identical. As for the content, this is nothing new to sacramental theology of any age. Mass is the action of Christ and the People of God, of the Head and Body, directed to God. It is also an opportunity for imparting grace to those who come to the Mass with a spirit of worship.