"- if the project settings specify task level for time sheets, then a resource assigned only in the staffing profile will not be able to report time;"
Regarding documentation (time mamagement users guide page 57) when I use these project settings:
Track time at the: Task level
Allow the following to report time on this project: Project resources.
So in dream world I should add resource to staffing profile and it is all. I can't understand why it is not working in this way. In documentation is also nice example table this is working. This is the case when I have resource who can participate on many tasks from huge workplan but I don't want to assign him to each task.
Also I found strange that when I assign resource to one random task, then this resource can see every task in work plan.