I haven’t nailed down the terminology, but this is an idea I’ve had on the back burner for years. I can’t imagine a better community to try and articulate it to than this one!
In sci-fi and fantasy novels, I find that my favorite books tend to follow one of two models. The expansive ones are so rich in details, both explicit and implied, that nearly every detail could be turned into the centerpiece of a novel of its own. (Revelation Space, by Alastair Reynolds, is an example of this.)
Focused novels, on the other hand, take one or two elements and fully explore how those elements would interact with (and change) the world. George R.R. Martin’s Song of Ice and Fire series is an example of this — there’s very little magic, but what magic there is has a tremendous, fully-realized impact on the story.
The reason I’m bringing this up here — apart from wanting some feedback on the basic concept (which, again, may be poorly articulated) — is that I think this has value as a model for worldbuilding. The Forgotten Realms setting for D&D, for instance, is very much an expansive setting, while Vampire (considered without the other WoD books) is focused on one element, the existence of vampires, and on exploring that fully.
Does this make sense? Am I onto something? Is it useful?