You don't need to have been reading the Itch for very long to know that when we're talking about prose, I'm usually going to talk about specificity - particularity of experience - precision. It's an aspect of Showing, as opposed to Telling, and a way of making even your Telling Showy. As I put it in that post, "Crudely, They met at the big tree isn't as Showy, because it isn't as particularised, as They kissed under the rotting willow, or They fought beneath the sapling oak". And so much of the power of the paragraph I was anatomising in "An Education in Writing" is created by the exquisite precision of Bowen's choices of mostly, in themselves, quite ordinary words.
But, of course, there's the other side of the business, which as I remember (my copy's taken a walk) John Fairfax and John Moat (founders of the Arvon Foundation) discuss in their brief but excellent The Way To Write. Sometimes, describing things specifically closes the world off for the reader: it leaves them no space in which to imagine. Sometimes you do want to write The man came over the hill, or They met at the big tree.
As my newly expanded post on Psychic Distance suggests, In the far-off days of Uther Pendragon, witches stalked the earth is no less effective, in the right place and to the right purpose, than something which evokes a particular witch's particular greeny-black rags and rust-patched broomstick. Similarly, I gather that writers of category romance are told not to be too specific about what the heroine looks like, so that the reader can read themselves into that role.
As I was exploring in "The Desirable Difficulty of Sleeve and Paint", when the reader is doing a larger proportion of the work, she or he comes to "own" the experience that is conjured much more completely. The rhythm of stress-and-slack, of action and recuperation, seems to me crucial; by leaving room/time to breathe in the telling of the story, you leave time for the experience to reach full strength in the reader. So maybe this question is part of the wider one which I keep in the mental file labelled "The pictures are better on the radio". It's specially crucial in writing sex scenes because the pitfalls of Too Much Stuff are so close together and, as we all know, the best sex in a book is the sex that happens in the reader's head.
In other words, what you're trying to get a feel for is when to supply everything that you want the reader to "see" (and smell, feel, understand...). And when do you supply almost nothing, leaving the reader to read their own experience into the spaces, and feel it that much more powerfully? It's tempting to assume that the latter is more effective, but sometimes it's just impoverished or bland, because the reader doesn't have much material of their own to read into that space. Besides, we read fiction in order to experience otherness - strangeness - whether it's to see our own world estranged, or experience an entirely other world. That's only going to work if you do give us enough for our mind's eye (ear, nose, fingertips, tongue) to estrange us from our familiar experience. And, finally, when do you positively want the reader to stay with the grand, plain, archetypal elements and figures of the great stories?
I'm interested to see just how many other posts this one connects to, but at the moment I can't find some over-arching idea or principle that can pull all of them together. There's something here about psychic distance (close-up detail when we're close-up to an individual voice and point-of-view) and yet it's not just that, when you're choosing between met/kissed/fought, or at/under/beneath, or tree/willow/sapling. Maybe it's about the very nature of fiction, which takes ordinary, quotidian, individual experience and uses it to fill story-forms which first evolved for the telling of great, archetypal myths. What we're talking about here, perhaps, is about the shift to and fro along that spectrum, from the scent of a snuffed candle, which might be the one detail that brings your story alive, to Apollo in his chariot.