His Eminence DarÃo Card. CastrillÃ³n Hoyos, President of the Pontifical Commission "Ecclesia Dei" has spoken Vatican Radio about the Motu Proprio and ZENIT reported it.
My emphases and comments.
Cardinal CastrillÃ³n Hoyos on "Summorum Pontificum"
Prelate Hopes Eucharist Is Not Motive for Discord
VATICAN CITY, SEPT. 13, 2007 (Zenit.org).- Cardinal DarÃo CastrillÃ³n Hoyos says he hopes that the Eucharist is never a motive for discord, but only love.
The president of the Pontifical Commission Ecclesia Dei said this on Vatican Radio today, the day before "Summorum Pontificum" — Benedict XVI’s letter issued "motu proprio" (on his own initiative) on liberalizing the use of the 1962 Roman Missal — goes into effect.
The cardinal spoke about the true meaning [Okay... I wonder if His Eminence used the phrase "true meaning" of if that is a gloss by Vatican Radio or Zenit, both of which are filters.] of the pontifical document.
Cardinal CastrillÃ³n Hoyos: I would say that John Paul II wanted to give to the faithful who loved the ancient rite — some of whom left to join Archbishop Lefebvre’s movement, but who later returned in order to maintain full unity with the Vicar of Christ — the opportunity to celebrate the rite that was nearest to their sensibility.
The Holy Father Benedict XVI participated from the beginning in the Lefebvrite question and therefore knew well the problem created for those faithful by the liturgical reform. [But this isn't just about those faithful. It is really about anyone for whom this older form of Mass is "nearer to their sensibility".]
The Pope has a special love for the liturgy — a love that is translated into a capacity for study, of learning more about the liturgy itself. [And action: he, as Pope, presided over a Synod on the Eucharist, and issued Sacramentum caritatis and Summorum Pontificum.] This is why Benedict XVI considers the liturgy from before the Council reform an inestimable treasure.
The Pope does not want to go backward. It is important to know and underline that the Council did not prohibit the liturgy of St. Pius V and we must also say that the Fathers of the Council celebrated the Mass of Pius V.
It is not — as many sustain because they don’t know the reality — a step backward. On the contrary. [If he says "on the contrary", then it is a step forward.]
The Council wanted to give ample freedom to the faithful. One of these freedoms was that of taking this treasure — as the Pope says — which is the liturgy, to keep it alive.
Q: What has changed, really, with this "motu proprio"?
Cardinal CastrillÃ³n Hoyos: With this "motu proprio," in reality, there has not been a big change. [I think this is a purposeful understatement. He is downplaying the changes. In fact, I think there is a very big change.] The important thing is that in this moment, priests can decide, [and this is the change! The truly remarkable point of Summorum Pontificum is that it emphasizes the rights of priests, but bishops. This is a huge deal for the bishops, of course, some of whom see that fact as a negative.] without permission from the Holy See or the bishop, to celebrate the Mass in the ancient rite. And this holds true for all priests. It is the parish priests who must open the doors to those priests that, having the faculty, go to celebrate. It is not therefore necessary to ask any other permission. [Priests.... get it?]
Q: Your Eminence, this document was accompanied by fear and polemics. What is not true about what has been said or read?
Cardinal CastrillÃ³n Hoyos: It is not true, for example, that power was taken away from bishops over the liturgy, because the Code of Canon Law says who must give permission to say Mass and it is not the bishop: The bishop gives the "celebret," the power [well... I am sure H.E. means the permission to celebrate. The power to celebrate comes with ordination. A priest must have permission is use that power. But I am splitting hairs.] to be able to celebrate, but when a priest has this power, it is the parish priest and the chaplain who must grant the altar to celebrate.
If anyone impedes him, it is up to the Pontifical Commission Ecclesia Dei, in the name of the Holy Father, to take measures until this right — which is a right that is clear to the faithful by now — is respected. [Yes... people's rights are now made clear.]
Q: On the vigil of the "motu proprio" taking effect, what are your hopes?
Cardinal CastrillÃ³n Hoyos: My hopes are these: The Eucharist is the greatest thing we have, it is the greatest manifestation of love, of God’s redemptive love who wants to stay with us with this Eucharistic presence.  This must never be a motive for discord but only love.
I hope that this can be  a reason for joy for all those who love tradition, a reason for joy for all those parishes that will no longer be divided, but will have — on the contrary — a multiplicity of holiness with a rite that was certainly a factor and instrument of sanctification for more than a thousand years. [I think we must be wary of the argument of the older Mass' value stemming from its antiquity.]
We thank, therefore, the Holy Father who recovered this treasure for the Church. Nothing is imposed on anyone, the Pope does not impose the obligation; the Pope does impose offering this possibility where the faithful request it. [I wonder what he really said. This sounds strange, but you get the point.]
If there is a conflict, because humanly speaking two groups can enter into conflict, the authority of the bishop — as written in the "motu proprio" — must intervene to avoid it, but without canceling the right that the Pope gave to the entire Church.