Just finished listening to it. I did not see any interpretation in a quick search which points to the, in my view, OBVIOUS interpretation that this is a story about the sexual abuse of children. Both formed angelic alters which were compelling because they were wholly insincere. They were fully disconnected from both childrens true core experiences, which split them, because they could not be processed.
What Miles did in school is, in effect, ask to “play doctor” with other boys. He told his teacher that he knew a bit about boys but wanted to know more, Those are the words and ideas his Headmaster too vulgar and shocking to repeat. Even if that sort of thing was common in Public Schools back then, it certainly was not in 10 year old boys.
The ghosts, in effect, were a distraction and a camoflauge. James, I suspect, must have known somethinv on the topic he could not relate.
And I will note that “premature sexual experience” was Freuds first, and best, explanation for “The Aetiology of Hysteria”. But he proposed it to an audience filled with guilty men, presumably, and he nearly lost his career at the outset.
Our world would probably make more srnse if he had been silenced. He set the recognition of, and treatment for, trauma back some 70-80 years.
William James, his brother, was a vastly more competent, honest, and diligent psychologist than Freud.
And although the ghosts were obviously real enough in the stories, they stand in well for the figurative ghosts that haunt the worlds of those who survive such abuse. They click from one world to another.
Altogether I think this is shrewd psychology and in effect a symbolic telling of a story that in that time could not be told any other way,
Those who heard, heard. Most would have been utterly unequal to it.