I suppose it depends on what you hope to accomplish. If one is to take a scholarly approach to the problem, Malcolm's answer is certainly the right one. On the other hand, I'm not sure all the folk singers who are well known enough to be making beaucoup CD's, thus disseminating their particular versions of Child ballads, have necessarily taken a scholarly approach.

In many cases variant versions arose because someone didn't quite remember the tune and/or lyrics to a song and thus sang it in their own fashion. If the singer was of sufficient stature in a region, that might become the version of choice in that region. When I perform a ballad (and, admittedly, my audience is usually only those in a given group on Paltalk), I tend to choose a tune that I like and that scans well to the lyrics as I know them. By doing so, I'm acting in a decidedly unscholarly manner, but I'm not sure that I feel too guilty about that.

That said, I'm also not too sure that including only the basic tune from Bronson and a verse of lyrics that scan well to that tune would be all that helpful. In many cases much nicer tunes and/or lyrics are to be found among the variants. Somehow, it seems to me that the main value of Bronson is in its totality, enormous as that may be.

As a matter of fact, I have an ongoing project of scanning the entire set so I'm not dependent on the local library when I want to refer to it. I've completed only the first volume so far. Interestingly enough, my wife claimed she'd buy a used set for me (at $1,000 the last time I looked) if I'd get the basement cleaned up. In four months, I think I've cleaned enough to merit about ten pages. So much for my priorities.