Ros Wood wrote:To be fair, all the notes are present in the Repetoire Multilingue which is used for the ceremonies in Lourdes and Arno tries really hard to make sure that all nationalities sing the correct notes in the choir. So the errors coming out of Lourdes are probably caused by people mis-hearing. I don't recall hearing it sung incorrectly in Lourdes.
I'm sure you're correct that it's all been caused by mishearing, but back in the 80s Décha himself was already singing it incorrectly and that's how people were learning it then. It has been said that Décha couldn't read music (I have no idea if that was true or not), so perhaps he learnt it incorrectly by listening to someone else. Chinese Whispers, anyone?
The Celtic Alleluia is also in use, sung correctly, in Zagreb Cathedral, but they sing it slower than I have ever heard in Britain. I don't suppose they are much influenced by the Irish.