Surely one of the best things about playing folk music is the wide range of different variations and playing styles. I personally only tend to play while on Live Role Playing events, either in the tavern or around the camp fire, and though its nice to be able to play the whistle or flute while some one else sings the song, but its just as enlightening to trade different ways of doing the same tune. Anyone who claims that there is a right way of doing tradition music tends to be the sort of person who is always right, end of subject, as far as they are concerned, and they are the people who end up stopping the music from growing and developing. Certainly listen to other peoples advice and suggestions, you know when something said will suddenly click and improve your playing, but generally I avoid people saying saying there is a right and a wrong - folk music by its nature is a fluid creation, and trying to stop that just impedes it