Sub-Projects vs Copy content
You are in the lead over more than one projects, need to be able to control and have an overview over their outcome?
So you combined sub-projects in one master file.
Changes to sub-projects are kept synchronized once saved.
What if you want to link activities from one sub-project with activities of other sub-projects?
In this case you have to decide what's more important to you: separate files or linking.
Combine documents by using copy content.
This creates a new project file, and copies all the content of the combined projects into it.
Each file content will be an activity group.
Changes to the main project are not transferred to the individual projects, and vice versa.
Projects requiring cross-links between different sub-projects, need to be combined by the 'Copy content'-option.