I have seen the same problem with cars that had a broken mount in the K member where the lower control arm shaft is mounted. The welded area is not very beefy there. The weld breaks loose, then the hole surrounding it starts to elongate. It is because of this that companies like Firm Feel came up with structural repairs to avoid it. Large washers are welded around the mount to spread out the loads, and the problem is likely to never occur again. Also, worn lower control arm bushings can shift things around sending the camber extreme negative when going forward, but then returning to normal by backing up the car.