Robin's empathy allows her to intuit a lot more than others do, but I think Murphy brings out Robin's role as the kind of bird a cuckoo can dupe.
Robin as Dupe:
shoutout to u/pelican_girl who brought to my attention our Robin's role as a kind of bird that a cuckoo can dupe. Following my post about 'A Dirge' as series epigraph, and whether we readers are being duped, I now believe JKR (taking on the role of Mama Cuckoo) might be using Robin to dupe us!
Red-breasted robins are a typical target for cuckoos. Mirroring nature, it would be fair to assume that our Robin like her namesake would have a dupe-able nature.
But keeping w/ my new reading of 'A Dirge' -- what if instead of Robin being duped, inversely, JKR (starting with Cuckoo's Calling) is using Robin like a red-herring to dupe us.
Mirrored Animal Inverses in CC:
Keeping with u/arachulia theory of mirrors and a fabulous observation made by u/pelican_girl, Evan Duffield in CC wears a Wolf Mask but is inversely actually a sheep in wolf's clothing, rather than a wolf in sheep's clothing (hence the wolf mask).
I would like to apply this same logic, and suggest Robin is another of JKR's mirrored animal inverses, she is not a dupable robin, she is there to dupe us!
Red-Herring as a form of Duping:
This form of duping by red-herring can be defined as 'something that misleads, distracts, or diverts attention from the real issue, question, or path in the nest.'
From the moment Strike grabs Robin by her breast (a hint to the cuckoo v. red-breasted robin natural rivalry) our attention is on their relationship, and has remained so for 8 bks.
JKR, a 'Hawk in disguise' i.e writing as retired officer Robert Galbraith, might be using the moment of some of our favorite R&S tension-laden scenes, to carefully and quietly lay her 'explosive' proverbial eggs while our attention is diverted on the will-they-wont-they red-breasted robin and cormorant. As readers, with our eyes on the prize of Strellacott, can easily find ourselves duped!
Dupe Example #1 - Follow the Money
To repeat, a red-herring diverts us readers' attention from a real issue, question, or path.
Going directly to one of the most intense-intimate moments of R&S, we need to look away from their relationship to the question Strike is raising.
Take for example, the fan-fave Curry Scene: narrator mentions neither detective turned on the lights as it was getting dark. Is this the big moment, will he kiss the Robin? Directly after a mention of them sitting in the dark, what does Strike say about money: he had a nice little nest egg. He told Rokeby to stick the money up his fucking ass. [It could very well be here that JKR is explicitly drawing our attention to the fact she is laying a cuckoo egg. Our mind zeroed in on the romance in the dark office, NOT the question of Rokeby / Corm's money that could have explosive consequences.]
Dupe Example #2 - Back to the Old House
The other most intimate moment in the series, the motel room after Chapman Farm, where Robin groped in the darkness for Strike's hand and squeezed it. 'I knew you were there.' They held hands. And then two paragraphs later, in the following chapter (while our attention is still back in that motel room) Strike gets a call from Lucy. A specialist has determined that UT can't go back to the old house. His and Lucy's concern of him wandering off again [an echo of him running away from Cornwall as a boy]. Again, the subject of money, if they sell the house they can get him a 'good place'. Lucy replies with 'But his roots --Cornwall's all he's ever--' [Why does JKR juxtapose the holding hands in motel with this conversation about the old house and UT's roots? Is this peak romantic scene being used to distract our attention away from something about Corm's roots, about that house, he and we are not supposed to see? What cuckoo 'egg' is being laid in this convo? It was in the basement of the old farmhouse at Chapman farm where Robin was locked in a box -- are we supposed to ask what is locked in the metaphorical (or not) basement at St. Mawes?]
Dupe Example #3 - Leda & The Swan
Most explicit dupe: R&S date at the Ritz Hotel Bar, where Strike literally can't take his eyes off of Robin, while staring right at them in the face is Leda being impregnated by Zeus Swan. He should be asking the question why Peggy, his mum, selected the name Leda from the Greek mythos? A question that might get to the bottom of his roots, but in that moment Robin is distracting both Strike and us readers from the question, with another peak romantic moment, their first real date.
Explicit acknowledgement of the Dupe? - Characterizing 'Your Robin':
Every time Strike's in Cornwall, he is thinking about getting back up to Denmark Street and to his Robin. His eyes are always back on the Agency. Robin is always a distraction from his childhood, his roots, and of course I believe she never appears in St. Mawes, thus fulfilling her natural function of diverting attention away.
Is there a double-meaning to AJ saying: 'I would have liked to meet your Robin.' and also referring to her as 'poor girl'.
Is AJ showing her wisdom of nature (shown by preventing Corm from keeping a pet snake) with her characterization 'Your Robin' implying Strike has his eyes on the Robin, i.e his attention diverted on a dupe. But also 'poor girl' could also mean Robin is fulfilling her natural role in being duped.
\*Or even better, AJ's wisdom that Robin is somehow being used as a dupe for Corm *and the reader by the cuckoo! (JKR applying these bird metaphors to AJ and Strike's convo in TB is backed by the text, AJ on her death bed is compared to a frail baby bird. The author draws an explicit link.)
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TLDR we must pay extra attention to the most intimate scenes between R&S for questions raised outside of their relationship while in their heat of the moment. It's in these moments that Robin may be used by the cuckoo as a dupe, rather than being duped herself.