Sounds like positional calling at least needs more development before it surpasses gendered calling[^1]. I think positional could surpass gendered calling because it's more flexible. It should even allow the creation of new forms that have more complex results by breaking the symmetry created by always having to refer to the left- or right-starting individuals as an indivisible set. Perhaps a mixed approach is optimal?
I think indicators like "the person with your right hand free" will likely compress to "with your free right hand" or "start a right-handed". Accounting for different variants of each movement will still be tricky, but during the teaching phase the expected variant can be indicated to soften that difficulty.
[^1] Quick technicality (you can ignore this if you don't care): the "robins and larks" scheme is still gendered, though it has the advantage of divorcing dance genders from social genders.
allow the creation of new forms that have more complex results by breaking the symmetry created by always having to refer to the left- or right-starting individuals as an indivisible set
Today callers do this by adding "1st" or "2nd": the "1st Lark" is the Lark in each couple that is going down the hall, and the "1st Robin" is the Robin in each couple that's going up the hall. If they want to refer to the whole couple they say "1s" or "2s", as in "1s lead down between the "2s".
Quick technicality (you can ignore this if you don't care): the "robins and larks" scheme is still gendered, though it has the advantage of divorcing dance genders from social genders.
While this might be technically correct (ex: Filipino has two linguistic genders, common and neuter) this is different enough from how most people speak about gender in dance that I think it's actively unhelpful?
In normal use:
Gendered calling: using male words for the Lark/Gent/Left-side dancer and female ones for the Robin/Lady/Right-side dancer. "Ladies chain", "Men by the left", "Ladies, leave him there".
Gender-free calling: using names for the roles that are unrelated to male/female. At this point, almost everywhere does Larks/Robins, but there's a bit of Leads/Follows.
Positional calling: not referencing roles at all. Theoretically within "gender-free calling", but it's rare to see it used that way.
In a contra dance when only some of the dancers should take an action, the caller typically identifies them by role: "Robins start a Hey for Four" (or "Ladies" with gendered calling). In positional calling, instead, the caller doesn't use role terms: "pass right shoulders to start a Hey for Four". While we often don't think of it this way, only the dancer currently on the right side would start a Hey passing by the right shoulder. It especially helps if this flows well from the previous figure: after a courtesy turn you can usually just say "Hey for Four" without clarifying anything about who starts it.
I wrote about positional calling back in 2019, but that was before I'd danced to it. I recently attended a dance weekend that used entirely positional calling, however, and now I have more informed thoughts!
This was in some ways a better-than-usual context for positional calling:
The callers (both of which travel nationally) were very experienced.
Being a dance weekend, ~everyone had danced before.
The callers were on board with the idea of positional calling, and enthusiastic about it. (This is second hand.)
And in others a worse-than-usual context:
Almost all of the dancers hadn't danced to positional calling before.
The callers were both newish to positional calling.
In filling a whole dance weekend with interesting dances you can't stick to the figures and transitions that are easiest to call positionally.
Looking at this from just the functional perspective of how long it took to teach dances, how quickly the callers were able to drop out, and how much confusion I saw on the floor, I feel like this worked much less well than role-based calling. For example, a phrasing I heard several times was to direct a call to "the person with their right hand free." Not only is this much wordier than "Robins" or "Ladies", but it's much less robust:
Say this comes after a Swing, where some couples kept a connection (and only the one on the right has their right hand free) but others didn't (and so have both of their hands free): many hands fours won't know who should begin the figure.
The interpretation of each call depends more heavily on the current arrangement of the dancers, so when people have made mistakes it's much harder to figure out how to get back on track.
The bigger issue, however, was that the callers often ended up using positional approaches to construct names for roles: "the people who ended the swing on the left", "the people who started the dance in the left hand role", or "left hand role dancers" as ways of saying "Lark" (or "Gent"). Mostly this is just wordy, taking more time and mental processing, but it could also be ambiguous when you don't know if the caller is trying to identify roles or current positions. I remember starting a regular duple improper dance, and they asked us to face our partner and take hands with our neighbor. Then they called something to the "people on the right". Did they mean the people currently on the right in each neighbor pair (Larks/Gents) or the people who started to the right of their partner (Robins/Ladies)? I remember this happening at least twice, intended one way in the first case and the other in the second.
I still had a great time dancing, and this didn't add enough delay and confusion to dampen my experience, but I'm really not a fan of this approach.
That said, I do still see a place for it: if you have an intractable divide in your community where some people strongly oppose gendered calling and others strongly demand "Ladies/Gents", positional calling can be a helpful compromise. Or if you're a caller that can't stand one set of terms but is often asked to call dances that require them, getting so good at positional calling (including dance selection!) that no one notices you haven't named the roles. But as a candidate for the future of contra dance calling I really don't think it's a good fit.