"the lyrics were adapted from a legend familiar to anyone living in Devon or Cornwall, which he put to a tune he'd heard in a pub session years earlier without recalling its title or who played it."


Carefully crafted just to avoid royalty payments or recognition to others and followed up with a healthy dose of publicity from a newspaper hound (a dying breed) who wouldn't know a folk song if he had one stuck to his traditional arse!
I would take comfort in the fact that while Seth Lakeman was lapping it up at an award show, the best Folksinger of all was probably driving through a snowstorm somewhere, heading for his/her next gig.