In my mind, everything is a project. That’s problematic unless we dispense with semantics. Multiple interests is closer to the mark, although I really do have a lot of client projects.
The real challenge is the AC.ID is easy to grasp. since I devoured everything you wrote on the subject, it’s stuck in my head as the ideal. (It meshes well with another tool that I use: Workona.) On the other hand, PRO.AC.ID is not intuitive to me.
For example, with PRO.AC.ID, each project could have a similar outline, where AC matches AC. If I want to search for an item, say a bit of reusable code, and I didn’t remember which project contained it, my search would have to include all projects, right?
In other words, if * = wildcard, then my search syntax would be *AC and that would potentially return a lot of results. (Assuming I stored my index in Simplenote.)
Or, am I missing a fundamental tenet of JD?