This resonates a lot. I've noticed cognitive load isn't just a developer problem — it hits solo founders running small teams just as hard. When you're context-switching between code, ops, support, and admin tasks all day, the mental overhead compounds fast.
One thing that's helped me: treating "cognitive budget" like a real resource. I block my highest-focus work (architecture decisions, debugging) into morning hours when my mental bandwidth is fresh, and batch all the low-cognition admin tasks into a single afternoon block. The batching alone cut my perceived overwhelm in half because I stopped paying the "switching tax" between deep work and shallow tasks.
The point about documentation reducing cognitive load is underrated too. Even rough internal docs save you from re-deriving decisions you already made weeks ago.