Paddy & the bhoys enjoy themselves, they don't need your money, and just do what they feel like doing with the music.
Not always my kind of stuff, mind you, but I do admire musicians who are willing to explore possibilities.
If someone were to tell me that a version of a tun I was playing was WRONG, I would, in no small measure give the unfortunate person a touch of pedigree, sorefingers.
Knowledge is your great saviour in these situations, sorefingers, and you have quite plainly shown that you may need to read up a bit more.
We're talkng levels of understanding here, sorefingers; if you need it explained to you, you don't understand. If you don't understand, no amount of explaining will ever make it clearer.
By the way, my fingers get sore from time to time too, but I have no need to remind myself (nor, I'm sure, do many others around here) of this fact every time we post.