Functional Capacity tests

My friend was injured in June '08 when he was climbing on to the forklift (he snapped both perineal tendons, had surgery where they could only re-attach one).  He went through months of physical therapy and non stop pain.  He isn't able to drive for more than a few minutes at a time without intense pain and has to walk at a very slow pace now.  The surgeon was ready to release him, however because of his difficulty doing the tasks he used to he is scheduled for a functional capacity test next week.  
What can he expect and does anyone have any advice?