Fr Hunwicke praises the move, Fr Sean has reservations, especially about removing Confirmation as a sacrament conferred by the Bishop.
I am an old trad and therefore favour most things from the first millenium. I certainly see the move by St Pius as being an act of rupture and quite a serious one which prepared the way for even more ruptures in the rest of the 20th Century. That being said, I must say the continuous catechetical process Liverpool proposes would fill me with terror if I were a lay person.
The main reason the Sainted Pope Pius broke with the ancient Tradition was because of his own Eucharistic piety: simply put he wanted to start a habit of not only regular but also frequent reception of Holy Communion. The assumption today is that this is always a good thing but it strikes me that from St Paul onwards the Church discouraged frequent communion thinking it lead to laxity. At the very least that at the Eucharist there were always those who did communicate and those who didn't:
"Therefore whoever eats the bread or drinks the cup of the Lord unworthily will have to answer for the body and blood of the Lord. A person should examine himself, and so eat the bread and drink the cup. For anyone who eats and drinks without discerning the body, eats and drinks judgment on himself. That is why many among you are ill and infirm, and a considerable number are dying. If we discerned ourselves, we would not be under judgment; but since we are judged by (the) Lord, we are being disciplined so that we may not be condemned along with the world.The Fathers are continually pressing for more and more reverent Communion, I am no patristic expert but it seems that by the fourth century very very few people ever received Holy Communion, except as part of initiation in the East and Viaticum in the West, if they were fortunate enough. The division between communicants and non-communicants shaped the ecclesiastical structures for both East and West. By 1000 AD Holy Communion was something for priests and monks and nuns, widows and virgins, and in the West was certainly one of the reasons for the imposition of celibacy (but let's leave that bone alone here).
John 6 of course says, "unless you eat... we will not have Life", but many would suggest this meant receiving once in one's lifetime, as seems to be the practice for many Orthodox who receive communion in infancy at Baptism after Confirmation and rarely ever again. This too is the reason, presumably, why most ancient Missals, like the Roman Missal simply do not have Rite of Communion for the Laity, it just did not happen very often. It was only after the Great Schism that the Fourth Lateran Council (1215) issued the Paschal Precept, which ensured - for the law abiding - at least an annual Communion, despite the statements of various Synods, as far as I know, this never happened in the East.
Getting back to the "Confirmation Debate", it seems that priests always Confirmed those who hadn't been Confirmed before giving Viaticum and Extreme Unction.