Yes, Steve, you are right, but let me clarify my point:
I know (more or less) how the windlass worked :) What I am relaying is my experience of not encountering that mentioned elsewhere than in the writing of a few people discussing chanties. I looked at diagrams of the mechanics of windlass in detail, but these mechanics of the tool would not say anything about how sailors actually moved their bodies when operating the tool. (Does that make sense?) And people just writing about sailors at sea weighing anchor are unlikely to have found it worth describing the body motions; they took it for granted. Only the timing of music to the work occasioned some people, like Hugill and Harlow, to make these notes. In my presentation at Mystic, on the _Charles W. Morgan_ windlass (2015?) I showed a video of film from the 1920s that shows the action. If you blinked while watching, however, you'd miss it!

So what I wasn't saying is that this information is totally unknown and we need to discover it, but that it is generally not known to people. I don't think (?) the people at Mystic really knew about this before I introduced it -- and those are people who have collectively had their eyes on a lot of maritime writing and film. The sole reason it occurred to me to say anything was that I was trying to match up chanties to their pacing etc. and was therefore forced to consider this issue and spotted the clues in Harlow etc.

Cotton-screwing action is covered in my paper on that subject (yet unpublished, but presented in brief at Mystic in 2019). All the data for it was in a manuscript article I tried to get published, but the journal thought all that techie stuff had to go. The music stuff in the article is considered techie stuff and the mechanical stuff is ANOTHER body of techie stuff, and there's barely an audience that can digest both at once! So I have to revise the article without all the rich data about the cotton-screwing practice that I gathered and, I don't know, maybe get a chance to re-include it elsewhere.

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I don't think -- though I recognize I'm strongly opinionated about this -- that "which tasks were designated for each chanty" is the best way to go. Chanties were chanties, and by that *I* mean (here comes my arcane opinion...) that they have a standard form. It's not a form that applies to "short hauls" on braces, for sweating up, for tossing a bunt, for boarding a tack... there are "other" chants/songs for those things. Where I admit that I am weird is that other people will want to group those items as chanties and I don't. I'm 1) fine with *calling* them chanties and 2) not arguing that some contemporary people might also have called them chanties; this is not about language/labeling for me, just about preserving a conceptual distinction.

What *I* reserve as conceptually distinct "chanties" are those that have the form of 99+% of halyard songs. This is a great body of repertoire. By contrast, the short hauls are of different, various forms and *very limited* in repertoire. Practically everyone you mentions buntin ascribes just one song (Paddy Doyle's Boots). Everyone who discusses hauling on a main sheet mentions only two, the practically interchangeable "Haul Away Joe" and "Haul on the Bowline." I think these were chants developed to customarily accompany those tasks and can be partitioned from the great body of interchangeable and flexible repertoire that is the "standard" chanty (if not the chanty itself). The standard chanty, I think, is not about designating songs to tasks. It's a song-form independent of tasks. Two shipboard tasks in particular -- halyards and windlass -- came to be where that song-form could thrive. There is no essential difference between a "halyard" and a "windlass" chanty. There was just that body and style of song, chanty, which actors found applicable to both their halyard and windlass duties. It was the advent to this style/body of song to ships that effected the new ubiquity of worksong singing, layering over the job-specific and hackneyed items like "Haul the Bowline". I don't think "Bowline" and "Sally Brown" were cut from the same cloth. It's only the discursive bringing of them under an umbrella, later, as "songs sailors sing while at work," that throws them together in concept and appears to make them related.

And as the idea of "songs sailors sing while at work" (not precisely the same as "chanties") continues, and the habit of putting song to use for everything continues, the newer capstan comes in. Its a task where you can sing anything. Some people would sing the familiar chanties and some would add other items. A new layer, then lumped by the likes of Hugill -- who threw in everything but the kitchen sink without really indicating that "Merrily We Roll Along" was an outlier.

The funny way to say it, then, is: heaving and hauling "songs-broadly" have some overlap. Their overlap, however, is because some hauling songs (the ones for halyards) are chanties and some heaving songs are chanties. Chanties are chanties. It's only an appearance of "overlap" when we've divided "heaving" vs "hauling", and we've only done that because of the presence of non-chanty items of divergent form and applicability.

Probably need some charts for this, maybe some Venn diagrams, ha.

In short: I think it's self-evident from the song's form if it is a chanty (by my definition). We don't need to know any designation of task. With items not having that form, we can easily pick out the non-chanty hauling songs, as there were only a few encountered again and again. On the other side, there are non-chanty heaving songs, many of which could be applied to windlass or capstan, the tempo being the main factor.

Traditionally, the presence of a grand chorus is a way to identify a chanty (not a heaving song!) sung at windlass and capstan from one sung at halyards. But that is not foolproof because, in a chanty, the grand chorus is an optional feature governed mainly by how long you need to work, not by what work action you are doing.