That isn't quite the point I was trying to make though.

I am not talking about somebody learning a song from one place and not telling people where they got it from in general. I am specifically talking about somebody learning an arrangement, note for note in some cases or very similar in others (see the examples I gave in the first post of this thread).

I don't care whether an artist gives you the whole history of a song or not, some do, some don't, and it's their personal choice at the end of the day. If the arrangement is all their own work then fine.

But I think it is rude bordering on theft to use somebody's arrangement and harmonies that they have quite probably spent many hours working on without at least acknowledging where you got them.

Completely different to the J-Lo example above where I'm sure her writers & arrangers get a hefty fee and sign a contract saying she can use their material. Nobody would expect a pop artist to do all their own arranging anyhow.

All the people who have replied above along the lines of 'but it doesn't matter really does it?', have you ever tried writing full 4 part vocal harmony to a trad song? Believe me, I've tried and it is hard work. Takes hours. Maybe its because I'm slow at it, but even so, even the most experienced of arrangers must have to give it time and thought. Is it fair to say to the people who've done that hard work 'oh well, it doesn't matter'? If the performer who was covering their arrangement thought it didn't matter, presumably they would have just used the first version as a source of tune & words and worked out their own arrangement, which for a trad song I don't have any problem with at all!