This may be a tangent but there's something else about multiple out-back courses that I just became aware of. I certified an out-back 10K course, intended to be doubled for a 20K. I assumed you put a cone on the start line and runners go around it for their halfway turnaround. But the guy doing the timing (using chip-timing) wanted that turnaround moved away from the start line so that runners wouldn't go over the mats and register a false finish. I didn't budge as this was the night before the race, I told him to use one half of the road for the turnaround and keep the mats on the other side for the finish. That's what he did. If I had measured for his layout preference, it seems that the course would lose its adaptability for various multiples of 10K. I wonder if others are finding that chip-timing is putting weird constraints on course layout? I also wonder if others share my impression that RD's are prone to just make "little" adjustments on their own when they can get away with it? (I ran this race so they had to do it right.)