Comment by jraph

I'll use (1) for when I have a restricted set of pages (say, the usual pages of a site, like home, contact, about ...); body is not in a separate file; and (2) when the number of page is dynamic, say, a site that displays recipes stored in markdown files.

(3) I don't know yet for sure how I'd do it today (I will soon normally), I suppose I would just write different scripts, that can call some shared code. For APIs, people expect something that looks like REST endpoints and I suppose I would return JSON or XML in REST endpoint, but the URL structure that looks good for REST wouldn't for a normal page.