This is tricky, because the dog takes two different paths around the barrel, depending where he/she is on the course. In a case like this, I would think you have to place markers so they do not get in the dog's way either time and yet mark the parameters as much as possible. It would appear to me that only one marker could be used that would be out of the dog's way each time around the barrel. My opinion is based on being the chief course builder a couple of weeks ago, working with the judge. The main thing you want to do is mark the parameters, but not get in the way of the natural path of the dog around the barrel. If you were to put a marker to the "south" of the barrel, it would be in the dog's way going from 17 - 18 - 19 (ER1) or 3 - 4 - 5 (ER2), for example. Others are certainly welcome to express their own opinions.
