Yes, thanks for the post, I agree with your argument. Not always, but very often, you can reduce the scope of your mental model to small chunks, write one at a time and unit test them and you will need less focus while you are working.
I use to relate to the comic strip but I don't find myself in this situation so often since I use more pure functions and unit tests. Besides, simply by working on the chunks (functions) you give yourself time to think about the problem.
When I try to think about the big picture, like about how my API will work with other parts of the system or how to improve the architecture of a project, I have found that diagrams and explaining the system in words (maybe a description of the system in layman words or just write down my thoughts about the problem in bullet points) helps a lot too to come back to the problem after lunch or any distraction.
Do you preer a physical paper or whiteboard, or do you use diagramming software?
For me: Always something physical, so paper (blank without any lines or whatever) or whiteboard. Diagramming software is clunky and slow compared to a pencil, and will block your natural flow of thoughts.
If I am trying to understand something pen and paper, because it is fast and it helps me think. If I am trying to create something for long term reference or I know that I might come back to the diagram in a couple of days and modify it because is something still evolving I try to do it digital.
Dia is fast and allows you to group, link and move things easily. I have tried ArgoUML but I don't really like UML and I just want the diagrams as a mind-map, not to generate code, so it looks overkill to me. I have also tried inskape but don't know the short-keys and I am slower.
Summing up: use whatever works for you, but I find that writing things down in whatever medium helps, you can not keep everything in your head and offloading to paper or just a bullet point list helps a lot to come back to the problem the next day or after some time.
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