Much can be learned from one example. The farmer who produces a lamb is required to tag its left ear. The farmer who buys from the producing farmer is then required to put his tag on the sheep's right ear. I ask a very simple question. What happens a year later if the original farmer buys back the year old ewe for his own production purposes? This happens all the time in small areas. Does he now put two tags? I could not get an answer to this question when I sought it. It is a classic example.