Project Resource Planning Question

Hi Folks,

Have a question on resource assignments to tasks. Here's what I am doing.

From the structure tab, I am going to the task and explicitly assigning 2 resource from the Engineer roles. As shown in the attached screen (resourceplanning1.jpg) 1 resource has 200 hrs and the other 300 hrs which brings to the total demand for the engineer role to 500 hours. However, when I go to the Resources > Staffing tab (resourceplanning2.jpg), I don't see the time being "booked" against the resource. I still need to do the distribution to do an actual hard booking for resources. It appears that the task roles tab hours are only used to calculate the total role demand and has no impact on resource booking. Is this correct? If so, what is the purpose of being able to assign planned by resource in this screen?

Let me know if my question is not clear. By the way, I am on PPM 5.0 SP8. I understand that SP10 and 11 does have some enhancements in this area, but not sure if it will help me.

Thanks,

Lashan