Snail, you are not under attack. When a discussion occurs, people like to ask questions. Nothing personal. Also, our responses are not directed specifically at you, but merely trying to stimulate discussion among everyone who reads this thread. Please do not take any offense, I would hope that you would enjoy the "conversation".

You said - "but if you've got the real thing on the front doorstep, isn't it better to learn it that way?"
Do you know for sure how that "real thing" learned the song?

As to "collections", I would think that the fact that the Copper Family was adding to its repertoire for generations before Brasser started writing them down counts for a collection. Isn't that the point of most collections? If the grandchildren are now learning songs that Brasser wrote down, is that any different from them going to a library and finding a song from another collection?