When using a single project file in the company , it can be really convenient to create temporary shortcuts to certain folders. If this could be done in the project file, then this would be an awesome solution. However, for that to work, users must have write permissions to that part of the project file while all other settings should maintain a read-only status.
When this could be done, users can create their own favorite folders shortcuts that are convenient when preforming 'Save As' actions. The user can set it, to a specific project, within the overall project folder. When he's done, he could set new values to the Project file so he could work more efficiently on the next job. Now time is lost to navigate to the correct folder. So being able to add those custom shortcuts is a time saver.