When I am coaching I refer to the trailer arm as the one that comes back on to the handle after the turn. So coming out of 1,3,5 this would be the right arm and coming out of 2,4 it would be the left. After you complete the turn and put your trailing arm back on the handle it is good to then begin to feel the pull through said trailing arm. By doing this you can feel the pull evenly, allowing you to stay balanced behind the boat. I was just looking for the mag to see what article you were talking about but couldn't find it. I will look for it again and see if I can clarify what was said there.