These sections were expanded considerably from 1975′s GIRM 56 & 108-109. For ease of reference, I colored sections new to 2000 in red:
147. Then the Priest begins the Eucharistic Prayer. In accordance with the rubrics (cf. no. 365), he selects a Eucharistic Prayer from those found in the Roman Missal or approved by the Apostolic See. By its very nature, the Eucharistic Prayer requires that only the Priest say it, in virtue of his Ordination. The people, for their part, should associate themselves with the Priest in faith and in silence, as well as by means of their interventions as prescribed in the course of the Eucharistic Prayer: namely, the responses in the Preface dialogue, the Sanctus (Holy, Holy, Holy), the acclamation after the Consecration, the acclamation Amen after the concluding doxology, as well as other acclamations approved by the Conference of Bishops with the recognitio of the Holy See.
It is most appropriate that the Priest sing those parts of the Eucharistic Prayer for which musical notation is provided.
148. As he begins the Eucharistic Prayer, the Priest extends his hands and sings or says, The Lord be with you. The people reply, And with your spirit. As he continues, saying, Lift up your hearts, he raises his hands. The people reply, We lift them up to the Lord. Then the Priest, with hands extended, adds, Let us give thanks to the Lord our God, and the people reply, It is right and just. After this, the Priest, with hands extended, continues the Preface. At its conclusion, he joins his hands and, together with all those present, sings or says aloud the Sanctus (Holy, Holy, Holy) (cf. no. 79 b).
149. The Priest continues the Eucharistic Prayer in accordance with the rubrics that are set out in each of the Prayers.
If the celebrant is a Bishop, in the Prayers, after the words N., our Pope, he adds, and me, your unworthy servant. If, however, the Bishop is celebrating outside his own diocese, after the words with . . . N., our Pope, he adds, my brother N., the Bishop of this Church, and me, your unworthy servant; or after the words especially . . . N., our Pope, he adds, my brother N., the Bishop of this Church, and me, your unworthy servant.
The Diocesan Bishop, or one who is equivalent to the Diocesan Bishop in law, must be mentioned by means of this formula: together with your servant N., our Pope, and N., our Bishop (or Vicar, Prelate, Prefect, Abbot).
It is permitted to mention Coadjutor Bishop and Auxiliary Bishops in the Eucharistic Prayer, but not other Bishops who happen to be present. When several are to be mentioned, this is done with the collective formula: N., our Bishop and his assistant Bishops.
In each of the Eucharistic Prayers, these formulas are to be adapted according to the requirements of grammar.
150. A little before the Consecration, if appropriate, a minister rings a small bell as a signal to the faithful. The minister also rings the small bell at each elevation by the Priest, according to local custom.
If incense is being used, when the host and the chalice are shown to the people after the Consecration, a minister incenses them.
151. After the Consecration when the Priest has said, The mystery of faith, the people pronounce the acclamation, using one of the prescribed formulas.
At the end of the Eucharistic Prayer, the Priest takes the paten with the host and the chalice and elevates them both while pronouncing alone the doxology Through him. At the end the people acclaim, Amen. After this, the Priest places the paten and the chalice on the corporal.
You can see the intent was to tighten up some loose spots and address issues perceived to be a problem just before 2000, such as the use of unauthorized prayers or acclamations. And handling the name(s) of bishops, too. Anybody see anything of particular note?

Under the notion of history, we have Biblical catechesis, doctrinal catechesis, and sacramental mystagogy. Perhaps you can help me shed some light on the last point, which seems to suggest the discernment of God’s revelation in the experiences of life.