As usual a provocative thread which mentions folk music degenerates into the old chestnut "What is folk music?"
In many ways the argument is futile in that it is carried out by groups with very different views of the world.
Academics, ethno- musicologists, field researchers, whatever you chose to call them will by the nature of what they do spend great time and effort in defining terms such as Tradition, Folk music, etc. This is fine, this is what they are expected to do by the various organisations and bodies supporting them. This group are an educated elite and very small in number .
When this group refer to the 1954 definition of folk music I am sure they are more than familiar with it and spend many a happy hour at conferences debating its meaning and possible re-formulations.
Non- academics, which I guess would include the majority of performers and audience come to the music in a relatively academically uninformed way, and if you were to ask any audience ( Mudcat excepted ) what the 1954 definition of folk music was 99% would not have a clue; and why should they, they are already listening and performing music which by their own everyday definition is to them Folk Music.
This is not to say one group is better than another just that the differences often mean that dialogue can often be difficult and fraught with misunderstandings.
Kate Rusby has recently released a new CD "while Mortals Sleep" which is a collection of Traditional South Yorkshire carols, tastefully accompanied by a brass quintet. I am sure it will sell well with many contented purchasers. Personally I like to listen to the carols in a crowded pub, surrounded by people who have been singing and thus preserving this living tradition for many years.
Preservation of these carols has been undertaken in the form of field recordings. Professor Ian Russell is a notable researcher making field recordings of carols (:1999 English Village Carols: Traditional Christmas Carolling from the Southern Pennines, CD, Smithsonian Folkways SFWCD 40476, Smithsonian Institute, Washington DC, fieldwork recordings plus 28pp article.)
I guess Kate Rusby's CD may be easy listening for him, but its academic interest in relation to the history of traditional carols is likely to be small.
This is obviously a somewhat simplified argument, as clearly some people will cross the boundaries between groups. For either group to attempt to dictate to the other is unreasonable.
The other issue which this type of discussion often degenerates into is what is a good singer/performer. I shall stick with the "beauty is in the eye of the beholder."