With a lecture I agree, that would be weird. I’m sure he gave a lot of lectures with scant notes as the ophthalmology instructor before this. I’m thinking this is the kind of thing where he was allotted 15 minutes to speak and had to make the most of it.
I’ve been listening to a lot of videos on the electric universe model, where they propose that a few planets were much closer to Earth only several thousand years ago, plainly visible in the sky, and they only recently moved into the present orbits. I’ll never be expert enough on that myself, but the overall model does bring to light many things about cosmology (the history of the universe) that are totally made up to plug holes in the mainstream theory because everything cosmologists predict ends up being wrong.

“Imagination and Vision” was read (by Bates?) in June 1921 and then published in October of the same year. So it seems that we have an oral discourse with a subsequent publication. Perhaps it was something like what used to happen when I did my degree which was that the lecturer gave all us students printouts of the day’s subject with him or her reading the text, going through it and explaining it to us which lasted usually about an hour. This Bates text could have been similarly used. A good teacher can take a short work like a poem and find so much meaning and explore its possibilities almost endlessly.

Incidentally as regards viewing celestial objects like Saturn, I have read that when Venus is in its crescent phase the keen-sighted can see it looking like a little crescent moon. Astronomers (both amateur and professional) are always moaning about light pollution from towns and cities but Venus shouldn’t be affected by that since it is so bright.

I think it’s a great illustration of how well imagination influences things. I’m not sure he’s 100% spot-on with his interpretation of why it works.
That makes sense with Saturn’s rings being more visible when they’re tilted more and look wider.
Most people prepare their speeches on paper to read, so I assume he just submitted his copy to publish?