Even more astonishingly, Abp. Müller also apparently holds a doctrine of Christ's presence in the Eucharist that is Lutheran (at best): the consecrated Species are not the true Body and Blood of Christ in his transfigured (risen) corporality; rather, the Lord just becomes "present" in what remains bread and wine.

Müller's view seems impossible to distinguish from that condemned as heresy by the Council of Trent (cf. Dz 884 = DS 1652). Pope Paul VI insisted on this dogma in his 1964 Encyclical Mysterium Fidei, and again in what he considered the most important document of his pontificate, the 1968 Solemn Profession of Faith. Here the Holy Father proclaimed: "Every theological explanation which seeks some understanding of this mystery must, in order to be in accord with Catholic faith, maintain that in the reality itself, independently of our mind, the bread and wine have ceased to exist after the Consecration, so that it is the adorable Body and Blood of the Lord Jesus that from then on are really before us under the sacramental species of bread and wine."

This perennial Catholic doctrine is repeated in the Catechism of the Catholic Church, ##1374-1377.  This is to say nothing of Müller's sympathies for the liberation theology of his close friend Gustavo Gutierrez, or his reported statement that "Protestants are already members of the Church" - a position that would be clearly contrary to Pius XII's teaching in Mystici Corporis as to what constitutes "real membership" of Christ's Church.    

The following is taken from Müller's Wikipedia entry.

Eucharist: In 2002, Bishop Müller published the book "Die Messe - Quelle des christlichen Lebens" (St. Ulrich Verlag, Augsburg). In the book, he says : "In reality, the body and blood of Christ do not mean the material components of the human person of Jesus during his lifetime or in his transfigured corporality. Here, body and blood mean the presence of Christ in the signs of the medium of bread and wine."

Liberation Theology Müller was also a pupil of Gustavo Gutiérrez, the “father” of Latin-American liberation theology, with whom he has a long and close friendship. Commenting on Guitierrez, Müller stated: "The theology of Gustavo Gutiérrez, independently of how you look at it, is orthodox because it is orthopractic and it teaches us the correct way of acting in a Christian fashion since it comes from true faith." It is important to note that Gutiérrez’s thoughts were never censured by the Holy See although it was asked that he modify a few of his writings.[5]

Mariology: In his 900-page work "Katholische Dogmatik. Für Studium und Praxis der Theologie" (Freiburg. 5th Edition, 2003), Müller says that the doctrine of the Perpetual Virginity of the Blessed Virgin Mary is "not so much concerned with specific physiological proprieties in the natural process of birth [...], but with the healing and saving influence of the grace of the Savior on human nature." 

May Heaven preserve the Church against the gates of Hell in this dark hour.