In the Project Management Professional (PMP®) process, a key part of the process is documenting what you're going to do.
So you write a stakeholder management plan which says 'this is how we communicate with our stakeholders' and 'this is where we keep our stakeholder register'.
When you're working on multiple projects, it can be hard to context switch. This applies no matter the project management methodology and Johnny.Decimal is no different.
So here's the idea: you write 'notes to self' that help you when you come back to this project later, and you keep them all in a predefined category.
Predefined as in the JD system dictates where it is and what it is for. The JD system reserves this category for its own use. So what do you want that to be?
It's obviously in 00-09.
00 is the meta-meta, so
00.00 Index . Leave a bunch of
00 for people to use themself.
09 JD management process? Then you can say
09.11 Whatever the title of this note-to-self and
09.12 Whatever else you think about and so on.
The point is that there is always one place that your brain can go when you jump back in to a project. It's your refresher, your safe haven, your knowledge that you left yourself a note describing where things were and it's okay.