There is no doubt at all that Murray Mcleod, Newport Boy, Davie and Mayomick, know what they are talking about from personal experience.
I have lost count of the number of times I have tried to learn a new song from a cd or orally and got the lyrics completely, though unintentionally wrong. It is a very easy thing to do. I have often been corrected and it can be a little embarrassing sometimes, nevertheless it is good to understand the lyric properly in order to deliver the song correctly.
This discussion has come about because someone in the past collected a word or phrase, and either misheard it, or wrote it down phonetically, and that then becomes the accepted 'norm'.         Maybe accent had a part to play. An Irish accent might well 'convert' a 't t' to a 'd d' [and ADD an unnecessary 'h' into the bargain. The Irish are well known for their generosity!!!]
I love folk music because it contains so many phrases, nouns and verbs that have fallen into misuse or disuse, and it's only through research and discussions like this that you get to the truth. I always get a big buzz from 'discovering' the true meaning of an antiquated word or phrase.