This endless lost of spec sections sounds a lot like waterfall. It's a formula for a gigantic document that one person writes and nobody ever reads. And when they do, the real world has already caused half of it to be outdated.
1. Describing the problem, the business value, and the key words/definitions
2. Defining the goals _and non-goals_ for the project
3. Describing the implementation's logic and data model (a simple schema with boxes and arrows)
I like how it is done in "Domain Modeling Made Functional". However I agree too much of this is counterproductive.
Is it just me or does a reasonable concern for documentation over time ossify into rent-seeking by corporate moochers?