RaphaCam said:
Oh, I see!

I think this is the original pronounciation of
г. Do Russians frequently change o to a and ye to yi when speaking Slavonic, as they do in the Russian language? Most professional videos I find online avoid this, but there's usually a gap between this kind of register and commonplace practice.
I've never been to Russia, so I can say only about Russians (or rather: people that their first langauge is Russian, so it's about Belarussians and some Ukrainians) reading (occassionaly) in Polish churches: they sometimes change "o" to "a", I've never heard "ye" to "yi" change; it's rather Ukrainian and Lemkos practice, but it's part of Galician pronunciation (that's not wrong, but just another variant).
RaphaCam said:
I suppose the Galician pronounciation is closer to Polish? So, are yus letters pronounced as nasals or are they equalised with ya and ye, as in other practices?
It's closer to Ukrainian (and Lemko language), not necessarily to Polish. Nasals are not pronounced in any Slavic Church, anymore. They used to be pronuncated maybe in XIII century :laugh: Especially, that they're not highliteted in the texts; I remember at my parish Church Slavonic lessons reading some texts in Old Church Slavonic, and it was the only time that we were reading nasals, because they w e r e in the texts.