Gigamaps are about sharing a sense of complexity. If the team members have a diverging sense of the complexity of the task, this is a problem. The person who thinks it is a simple task will allocate far fewer resources to the project than the person who thinks it is a very complex task. Aligning and making sense of such overall conceptions of a task we call sense sharing.
There are other types of sense sharing, including the sense of needed effort, the sense of resistance to the project, the sense of time needed and so forth.
Gigamaps are about more than just mapping out facts, entities and relations
Sevaldson, Birger (2015). Gigamaps: Their role as bridging artefacts. Proceedings of Relating Systems Thinking and Design (RSD4) Symposium. https://rsdsymposium.org/gigamaps-their-role-as-bridging-artefacts/
Sevaldson, B. (2018). Visualizing Complex Design: The Evolution of Gigamaps. In P. Jones & K. Kijima (Eds.), Systemic Design: Theory, Methods, and Practice (pp. 243–269). Tokio: Springer. https://link.springer.com/chapter/10.1007/978-4-431-55639-8_8