Jeff Rice writes about situation in the teaching of writing, noting the importance, as a writer, of recognizing one’s situation within a network. Yes, of course, we always talk about the "rhetorical situation," the well-worn rhetorical triangle with its counter-intuitively four(?) parts: author, audience, context, and medium. But that rhetorical situation has been a commonplace and as such hardly a "place," a situation, at all.
Classically rhetoric is in/of the agora: the marketplace, the crossroads. Yet the academy, classically, is not, and writing pedagogies, including textbooks, have generally sought to remove composition from the marketplace, to purify the writing process, (as I said earlier) to suck the air out of the writing classroom. Rice is right in noting "a textbook always feels like the last place to find intersections." Unfortunately (at least from some perspectives), writing can’t really be extricated from the market. It’s value is always a market value, unlike the imagined absolute value on the constative statements of science.
More importantly, writing always occurs at a material intersection. There’s a symbolic-informational network participating in every compositional event. There’s also an embodied, cognitive, material network (interlinked with that symbolic-informational network) in every compositional event. All the cultural-ideological matters we discuss unfold within these networks. They are apprehensions of these material, networked events, which feedback into the event (which is how ideology shapes composition–apprehending yourself as a "writer" shapes the events of composition).
So this leads us back to the crossroads.
The crossroads, as we all learned from Robert Johnson, is the site of supplication: pray to the lord and sell your soul to the devil. The crossroads of compositional events is the site where the fantasied, independent authorial mind intersects with the cognitive demons of the mediascape. It’s not magic, and it’s not romanticized. It’s a recognition of the permeability of the presumed boundary between the inside and outside of thought. Perhaps you can apprehend some of the affective vectors intersecting a compositional event and put them to the question, pin them on a grid of rhetorical tropes, name them as citations, or call them inspirations. But, of course, you can never capture them all.
That doesn’t mean that you can’t teach writing. But it does mean that you can’t capture it, purify it, and put it in a textbook. It means that you learn to write in the marketplace, at the crossroads, even though there are risks.