For me, success means "robust structural intuition". Perhaps frame it as understanding that's robust to adversarial noise? To fuzzing testing? If you fuzz content, changing numbers, inserting negations and lies, how extreme before there's a "wait, that doesn't make sense"?
Merely quantitative isn't sufficient. An Ideal Gas Law chapter problem, with numbers for solid Argon - mindless plug-and-chug - is not this success. But a sense of reasonable values, yes. Contrast the first-tier med student, asked for red blood cell size, who failing to recall it as a factoid, is quantitatively lost, retreating to "really really small".
Similarly, "descriptive" can be deep structure and constraints of a domain, focused on building structural intuition, or at least trying for it, or an embrace of "stamp collecting" focused on regurgitation.
I nod to "foundations for subsequent study, with the intended outcome that students have a broad but shallow understanding of core basic ideas. Lots of biology makes intuitive, mechanistic, and visual sense, much like [...] introductory chemistry. [...] without the broader context the understanding would be relatively fragmented, lacking the big picture." But then contrast it with content presenting a not-broad and quite-shallow take, that pervasively fails to engage with the domain's core structure. And then, even on its own shallow terms, still fails outcome-wise: First-tier institution students, coming to intro genetics from intro bio, lacking even a firm grasp of central dogma? Stoichiometry students not even thinking of atoms as real physical objects? So I see "wonderful books" and think "wat?!? - how about profoundly and pervasively dysfunctionally unhelpful books?".
Perhaps at root, there might be different visions of what a "big picture map" best looks like??? Maybe picture a human surface map, vs a USGS topography and geology one. Do details clarify by exposing patterns, or obscure as clutter? Does underlying structure? Do year-to-year research insights provide opportunity and motivation for frequent rewrites, or is there relative stability and slow evolution? Are labels and vocabulary treated as foundational, or as relatively unimportant? If you haven't seen part of the map, how important is being able to sketch it in plausibly? If fragmented into puzzle pieces, how important is being able to fit them together? How important is seeing why things are the way they are?
Maybe the contrast between a slim tourist guidebook, versus walking in conversation with someone who deeply understands the history and society and structure of a city? Both are accessible experiences. Conversation that's numerate will be richer than non. But while the guidebook can provide a bit of orientation, it's not even trying to leave you insightful and deeply clued in.
Thanks again. I'd not thought of the fuzzing analogy before.