If you actually understood the history of this music you'd know that Cecil Sharp never suggested any chords.

If you don't care how folk music came to me - don't give a damn which tunes were meant to be danced or marched to and how, which are associated with particular stories, particular moods, particular kinds of statement - how on earth can you expect to know anything about what the tune expresses? Good luck playing your arrangement of "Marching through Georgia" in Glasgow.

The original question wasn't about "individual takes" but the exact opposite - identifying the way things are usually done so as to fit into to it. How not to be original. Nothing wrong with "individual takes" in other performance contexts, but they aren't what sessions are usually about.

There is one basic mismatch between the way jazz performances are put together (these days, anyway) and folk tunes, which needs to be sorted out if you're trying to synthesize them. Modern jazz theory uses a "chord/scale" model, where a composition is presented as a chord sequence and a melody over it. The melody is then treated as not much more than a hint of how to continue - as each chord comes along, you can take off melodically into anything that fits the modal scale associated with it (and those modes are often nothing that ever occurs in any folk idiom from anywhere) or harmonically extend the chord in any vaguely compatible direction. Maybe you quote bits of the melody, maybe you mutilate it so much that its own mother couldn't identify the body. This is a very, very long way from folk practice. It's basically an art music discipline, like the Indian raga or Arabic maqam. People who manage to create music that sounds like *both* jazz and real folk music *at the same time* are few and far between and spend a very long time working their music out with a small group of collaborators (Jan Garbarek, Okay Temiz, Bojan Zulfikarpasic, for a few). They also know the folk material they're using very well indeed.