I think that this is a nonsense song that is not intended to make any sense. Chezzetcook is not in Cape Breton but on the mainland in Halifax County. The "Black and Tans" was the nickname of the Royal Irish Constabulary which had little or nothing to do with Cape Breton. Most other parts of the song make little sense as well. In the old Gaelic Cape Breton and Scottish tradition words would be put to a fiddle or pipe tune in nonsense rhyme in order to sing the tune; "Port a beal" or mouth music is what it was known. I believe this song to be an English version of that. As stated it could very well include parts of older songs.