Regarding Chappell's attitude to Scottish ballads, this is only my own theory based on wide reading, Chappell's attitude comes out more in his editorship of The Roxburghe Ballads completed by Ebsworth who shared this view. Other near contemporaries and earlier, mostly English, but some Scottish, like Ritson and Chambers, thought that a large percentage of the Scottish ballads had been written by the Scottish literati and there is plenty of evidence to suggest this was rife (Lady Nairn, Lord Hailes, Elizabeth St Clair, even Mrs Brown perhaps) following in the wake of Percy (who was English). Of course, except where a few were found out and confessed, there was very little proof. If someone makes up a ballad using all the standard characteristics and their mates make up a few variants for good measure, unless in the unlikely case of any evidence surviving, where is the proof?