I'm pretty sure that it was the Clare Brothers who referred to the dancing on the cliff as a 'Pagan ritual' as Alec was not introduced until the next chapter - indeed, Alec was at a dance himself later in the programme.   The Clare Brothers (youngest is Angel, watch out for him later), were sons of a 'Blood and Thunder' priest in the far west of the county, and were themselves at University in training for the priesthood. The women dancing would have been anathema to their modern and mysogynistic Bible teachings (bearing in mind this was written in the 1870's and probably meant to represent the earlier years of the 19th Century). They were "educated" so they would have been more used to 'classical' arrangements, but I feel it was the dance itself, not the music per se, that was considered the pagan ritual. Mind you, 'pagan ritual' is not a phrase that Hardy would have used himself... he became increasing agnostic throughout his life. His actual phrase to describe the scene is 'country hoydens' but it's to be supposed that more people recognise pagan than hoyden.

And I object to the use of 'peasant' to mean 'rough', 'unfinished' or 'sloppy'.... these musicians would have provided all music for social gatherings, church services, weddings, Christenings, funerals, dances and such like. There would be a significant amount of time to practice, especially in the winter months and for the older members of the group. They learned their tunes by ear, and woe betide anyone who played out of order. Instruments were handed down from father to son, along with the tunes and their dynamics. It may not have been what the Clare Brothers were used to, but that doesn't mean it was played with any less skill or precision.

LTS - whose ancestors were the very 'peasants' that Hardy was writing about!