Well obviously they change the length of the camber link and i suppose it could change the rate of which camber is gained depending on the angle of the camber link relative to the arm. i Almost always use the 1,b location and every so often depending on the track i will go to 1,d or 2,b. If you are running at camber link location 1,B thats the inner hole on the rear camber block under the shock tower and B is the front middle hole on the hub, this is a fairly stable camber link location and if you were to move it to the A hole (lol) that will bring it to the inside front hole in the hub and this will dramatically effect rear traction, you should end up with less rear grip and a car that will rotate or steer with the rear faster and the oposite if you move it to the C hole or the E hole which is the outer hole in the middle row. So in other words a longer link will slow rotation down and usually add more rear grip but could cause your car to push if grip is high enough. I know thats not the best explanation but nobody else chimmed in yet so thats my explanation. Know the difference between the two inner holes (1,2) is alot different. The 2 hole (outer hole on camber block) has a big difference between the 1 hole, the 2 hole will let the car react a lot faster but be harder to tame as its fairly aggressive.
A real world explanation was exactly what I was looking for. Thank you.