Plenty of things come to mind, some of which might even be correct. Bad bushings in the rear suspension will indeed affect how the car travels down the road. Bad bushings in the front will also preclude getting reliable numbers out of an alignment job. I'll presume that Les Schwab had the good sense to check the inflation pressure on all four tires before they started anything. My experience of those folks is a good one. Has you buddies car ever been involved in an accident? He could have a bent lower control arm, or perhaps the chassis has suffered some damage that makes the car not track like it should. It may take some sleuthing and money to track this down. Just remember that the diesels aren't worth much, even when they are running and driving well. Good luck, and keep us posted with any progress or revelations.