> how do humans maintain a coherent mental model of a software system
This is the core question and it is wrong. Because it focuses on the software system rather than the problem you are trying to solve. A better version would be:
How do humans maintain a coherent mental model of the solution they want to create?
You need to have a picture of the whole process and everything related, not just your architecture and code.
This is the core question and it is wrong. Because it focuses on the software system rather than the problem you are trying to solve. A better version would be:
You need to have a picture of the whole process and everything related, not just your architecture and code.