Wincing Devil, I agree with the premise that there is no right or wrong or definitive version of a shanty (to a large degree anyway, there are of course exceptions) and Hugill explains this in some detail. The shanties given in his book are not HIS shanties, but shanties collected from singers and other collectors that he personally has vetted, in his own way. I love the new verse for "Rolling King", "Ruler King" or, as seems to be most popular nowadays "South Australia" (to my mind another shanty altogether) but wonder why you state that it is a hauling shanty, when Doerflinger, Colcord, et al. give it as capstan or pumps? It is THIS definition of what a shanty is used for that smacks of being definitive, saying that a shanty was used for one particular purpose. There are them as what was used for one job only, but the great majority were used for any damn thing that seemed appropriate at the time, by the person or persons singing it. I daresay that nearly all shanties have been sung at capstan and pumps at some time or other, as the tasks were often long, laborious, and downright bloody boring. So sooner or later the whole repertoire of shanties would be used up.
Thanks again for new verse, will add it to rest next time I sing this shanty. But I don't sing Nancy Blair anymore, not since the obvious and popular connection with Tony's missus. It's Nancy Brown for me, from now on.
P.S. To me, "South Australia" is the shanty known by the hoi palloi as The Cape Cod or "Codfish" shanty.