I used to own the English edition of the book (but unfortunately lost it in a fire five years ago). At least as interesting as the oft-quoted passage about the New Mass being a "banal, on the spot fabrication" of the introduction to the French edition was Cardinal Ratzinger's description of Monsignior Gamber as "the one scholar who, among the army of pseudo-liturgists, truly represents the liturgical thinking of the center of the Church." I'd read the book (and that quote) early in the Benedictine pontificate (around 2005-2006) and it gave me cause for a great hope that Benedict, seeing Monsignior Gamber as the representative of the liturgical thinking of the "center" of the Church (however loaded that political term now seems in hindsight), would therefore implement the Monsignior's plan for liturgical reform as laid out in that selfsame book.

In a nutshell, the Monsignior envisioned an establishment of the Traditional Latin Mass and the Novus Ordo as two distinct, separate Rites of the Roman Church. The Traditional Mass would be established as what it has ever been since St. Pius V's Quo Primum - the normative liturgical rite of the Roman Church. The Novus Ordo would be officially designated an "ad experimentum" rite and would be permitted to exist in every Roman rite parish only in a limited capacity (the TLM being normative) and only for a definite period of time - perhaps ten years - at the end of which, the fruits of the "experiment" would be measured and the future existence of the Novus Ordo would be based on those fruits. Naturally, in such a scenario, the objective fruitlessness of the Novus Ordo (unless we're talking about fruits of the Rembert Weakland variety) would result in a declaration of the resounding failure of the "ad experimentum" rite and the Church would return fully to the TLM as the one and only rite of the Roman Church.

As I said, Cardinal Ratzinger's endorsement of Monsignior Gamber filled me with hope that he would, as pope, implement this blueprint for restoration of the TLM. Instead.... we got Summorum Pontificuм in 2007, an utterly diluted, mealy-mouthed "allowance" for what St. Pius V had already made mandatory under pain of excommunication and the Wrath of Saints Peter and Paul and Almighty God Himself. And perhaps the very worst thing wrought by that motu proprio was the whole "ordinary form / extraordinary form" bit of hatefulness, which not only runs absolutely counter to Monsignior Gamber's infinitely saner call for the establishment of these two objectively different rites as two officially different rites, but, worse, dares to dismiss as a merely "extraordinary form" what St. Pius V spoke thusly about:  

We specifically command each and every patriarch, administrator, and all other persons or whatever ecclesiastical dignity they may be, be they even cardinals of the Holy Roman Church, or possessed of any other rank or pre-eminence, and We order them in virtue of holy obedience to chant or to read the Mass according to the rite and manner and norm herewith laid down by Us and, hereafter, to discontinue and completely discard all other rubrics and rites of other missals, however ancient, which they have customarily followed; and they must not in celebrating Mass presume to introduce any ceremonies or recite any prayers other than those contained in this Missal.

Furthermore, by these presents [this law], in virtue of Our Apostolic authority, We grant and concede in perpetuity that, for the chanting or reading of the Mass in any church whatsoever, this Missal is hereafter to be followed absolutely, without any scruple of conscience or fear of incurring any penalty, judgment, or censure, and may freely and lawfully be used. Nor are superiors, administrators, canons, chaplains, and other secular priests, or religious, of whatever title designated, obliged to celebrate the Mass otherwise than as enjoined by Us.

Apostolic Constitution Quo Primum, 14 July, 1570