Yes this is true. One other thing to look at is fence lines. If you line up a old fence line by eye and look down the line you can see quite small ground shift

Yes this is true. One other thing to look at is fence lines. If you line up a old fence line by eye and look down the line you can see quite small ground shifts. If you do use this make sure you crosscheck with other fences close by to make sure that any deviations are not just due to incompetent fencing.