This is thinking out loud, not doing anyone down or dismissing their ideas, just think of it as a discussion over a virtual beer (cup of tea and a slice of cake etc) there is no right or wrong just thrashing out possibilities.
Like I said, just a theory. I've been through loads of possibilities and I still keep coming back to why!
Yes they could be a scoop, but why use one if you have a knife which will process the apple so much easier plus you'd need a fairly stout knife take the meat off, process/eat the mutton in the first place and to make the thing. Plus if your teeth are that bad you'd have to peel the apple, and it won't do that, or cook'em and mash 'em in a mortar.
Over the years I've learned to take Ms Hartley's writings* with a(large) pinch of salt, when she is talking from experience it tends to be 1930s-50s Yorkshire or the bit of Wales she lived in, she makes huge leaps of faith with stuff and often she fails to give sources or proof,but that's just me.
Again, like I said I've used it as (Derek) a corer and it does a fair job, it does have a tendancy to split the apple if you don't 'wind' it in slowly and even on small 'funsized' pippins it takes two bites of the proverbial cher...erm apple once from each end to remove a core easily next time we roast mutton,which may be quite soon.....Mmmmmmmmmmroast mutton, I'll have the bone and have a go at making a longer one see if that helps, plus to be really effective I'd need to thin the bone down to an edge all the way up to the horizontal cut
Some other possible uses could be;
A marrow scoop for taking bone marrow out of big bones.
A guide for filling gut when stuffing sausages.
The website of a well known Anglo-Saxon group has it as a possible cheese tester.
Any and all of the above, a useful multipurpose thing.
Possible horse harness or religeous/ritual purposes
Gwan, some of you lot make one, see what you can use it for
Mebbe I should've bunged it in General History gubbins, waddaya think MODs?
*Take a gander at her Medieval Costume and Life and see how much still holds up today.
Futuaris nisi irrisus ridebis.