What is the difference between Chrismation and Confirmation?

The mystery of anointing or laying hands to invoke the Holy Spirit after baptism is called Chrismation in Eastern Tradition and Confirmation in Roman Catholicism and other Western traditions. It is attested in the Scriptures and in the earliest Christian writings.
A significant difference between the two is that in the West, Confirmation was eventually separated from Baptism, whereas in Orthodox Christianity, Chrismation has always been done right after Baptism, because the Lord himself was anointed by the Holy Spirit in the form of a dove right after his ascent from the Jordan.
The separation process in the West is mainly linked to the desire to maintain the bond between this rite and the bishop. The Western view was that only the bishop could perform this rite, not the presbyter(s). This was a major point of contention between Latins and Greeks at the time of St Photius (Patriarch of Constantinople) who wrote the following in 867:
The first error of the Westerners was to compel the faithful to fast on Saturdays. (I mention this seemingly small point because the least departure from Tradition can lead to a scorning of every dogma of our Faith.) Next, they convinced the faithful to despise married presbyters, thereby sowing in their souls the seeds of the Manichean heresy. Likewise, they persuaded them that all who had been chrismated by presbyters had to be anointed again by bishops. In this way, they hoped to show that Chrismation by presbyters had no value, thereby ridiculing this divine and supernatural Christian Mystery. From whence comes this law forbidding presbyters to anoint with Holy Chrism? From what lawgiver, Apostle, Father, or Synod? For, if a presbyter cannot chrismate the newly-baptised, then surely neither can he baptise. Or, how can a presbyters consecrate the Body and Blood of Christ our Lord in the Divine Liturgy if, at the same time, he cannot chrismate with Holy Chrism? If this grace then, is taken from the presbyters, the episcopal rank is diminished, for the bishop stands at the head of the choir of presbyters.
This Western position may be connected with the view that only the bishops are the apostle’s successors (not the presbyters), which is not the Eastern, and we would argue primitive or biblical, view.
Because the bishop (in West) could not be there for every baptism, the faithful had to wait, sometimes for many years, until the bishop could come and do a mass confirmation. This led to the practice of receiving Holy Communion (“first holy communion”) before being Chrismated / Confirmed, that is without being fully initiated. It is to be noted that since Vatican II, Roman Catholic priests are allowed to perform confirmations with holy Chrism (like the Orthodox), but the (erroneous) tradition of not confirming infants after baptism remains. The Orthodox would also argue that the Latin form of baptism, which makes pouring normative, is defective, just as the invocation of the Trinity understood in the Latin theology of the filioque is likewise defective.
Moreover, the Western tradition also developed the idea of an Age of Accountability — that somehow someone cannot be a full member of the Church until such time that they can rationally choose to be a Christian.
In Orthodox Christianity, anyone can be a full member of the Orthodox Church regardless of age or mental capacity — they can freely partake of all the sacraments available to a member of the Church.