I've done some big document projects.
Example: I and three others re-wrote and published the "Owner's Manual" (System Information Manual) for the trans-Alaska pipeline in Frame. Four writers, four years, 44 volumes, who-knows-how-many thousands of pages. Frame coordinated all very well, never had a problem. It was the first desktop system we ever tried -- had used IBM's VM publishing (tagged script) up until that point.
I still use it on every project, although I've moved to PC for the publishing nowadays. We all feared Adobe would make big changes when they bought out Frame, but really nothing much has changed since v.5.1. -- just better performance, incorporation of the (formerly optional) web tools, etc.
It's a shame they won't be putting it on Mac anymore, but it works just fine on PC, too....
Best. Technical. Document. Tool. Ever.