Many years ago I was in the Pram Factory (Melbourne) after the conclusion of their season performing the (then) new translation of the Oresteian Trilogy. We had to bump out that night and all the cast and some friends set to work. I ended up working in the rafters dismantling the lighting, one part of which required about 10 of us, in a line along a beam very similar to a yard, having to pass a heavy loom of about 50 electrical cables along the length of the beam. The only effective way to do this was to have us all lift it in unison and move it the 12" or so across the front of our bodies, repeatedly.
The group was uncoordinated and ineffective until I started singing a song that most Australians learned at school; "South Australia".
To be fair, I was well experienced at leading songs and had been known as a shanty singer but, for me, it was a rare occasion when the work at hand really called out for a shanty. It worked perfectly. And, I later found out, others used the same technique at later bump outs. I suppose they were led by someone who'd been part of that Pram Factory crew.
I'd suggest that the subsequent singers acquired and performed such a role exactly as had earlier seamen. It's a while since I read Hugill but much of the Mudcat chat about shanties seems to concentrate on how things were done on the larger ships. I suspect smaller, coastal vessels might also have influenced how people learned maritime things too. Before they got nylon ropes and high geared capstans, that is; shanties are pretty much a lost cause on racing yachts.