It's not true that the early collectors/anthologists of folksong were practical musicians interested in singable material. Essentially none of them were, either in the British Isles or in mainland Europe. They were mostly antiquarians documenting local culture, or in some cases landlords documenting their tenants' music in much the same way they went about cataloguing the monuments on their land or measuring crop yields. The competitive incentives to "improve" your local song harvest by cheating were much like those of a Stalinist farm manager weighing spuds.

Scott did an effective job as consultant-antiquarian-for-hire to the Scottish gentry, but was totally tone-deaf and couldn't have any useful opinion about practical singability. Any sightings of Percy leading a pub singalong?