My copy of the missallete, which is the template that most choirs use to sing on Good Friday, contains no mention of the Reproaches at all. We instead are instructed to sing a song written in 1976 (with a chorus that sounds a bit like the theme to Gilligan's Island) or to sing "other appropriate songs."
The GIRM contains no instructions on the matter, but I've yet to discover evidence that the Reproaches have been abolished or are even optional.
The Reproaches are still in the Graduale Romanum. Many things appear in this book that are rarely used so perhaps that is understandable. However, the Reproaches are also printed larger than life in the Sacramentary itself, taking up three full pages with music. So let no one say that it was the 1970 Missal that caused them to disappear.
I gather that most celebrants skip over these pages since the music is for the choir to sing, not the priest. In some ways, it is a puzzle as to why they appear in the Sacramentary at all since this book doesn't print other chants that are exclusive to the choir, such as the Offertory proper at every Mass.
But, as I say, there is no mention of their existence in my missalette at all. And let's face it: if it is not in this fly-away book, it will not happen. That's how much influence these publications wield. These private companies can wipe out whole swaths of the Roman Rite just by declining to print things. After 10 or 20 years, no one remembers that it was ever sung.
It seems Orwellian in some way, but I actually think it is a reflection of the chaotic system of: 1) endless numbers of choices over what to do at liturgy, 2) the lack of rubrical specificity in the ordinary form, 3) the way the parts of the Mass are sprawled out over so many books, 4) the remarkable and pervasive ignorance concerning the role of the choir at Mass, and 5) the way that the Missalettes are targeted for use by the people and tend to be inattentive to the parts that belong exclusively to either the celebrant or the choir.
In this thicket, some things gets lost.
The Reproaches are an important part of Good Friday because they highlight the essential injustice of the Crucifixion, the culpability of humanity in this action, and the role of sin in those times and our times in bringing this about. We are given remarkable gifts by God, and the signs are all around us, and yet we do not show gratitude. Rather, we turn our backs on God and deny God due reverence in our lives and in our worship.
The narrative of the Reproaches is presented as a historical epic but it is impossible to hear them and not think of the universal ethical and theological implications. When we leave them out, we are refusing to let the Christ of all history speak to us, saying perhaps what we do not want to hear but we must hear.
Our own choir has always used the Victoria setting of the Reproaches, the most popular since the Renaissance. The use of the Gregorian setting from the Graduale is also common among parishes that still use the Reproaches. This very beautiful English edition from Palmer/Burgess is also an option. You can see the entire Good Friday service music in the Plainchant Gradual.
For big occasions such as this, the normal tendency of parish choirs is to stick to the missalette and dig through the archives for something tangible that was put together by a music director who left the parish years ago but whose legacy survives and is revived every year. This year, please consider a new approach.