I measured a 5K not long ago where I had to add an out-and-back section that required crossing an opening in a barbed wire fence so that I could get in enough distance. There was only one spot to cross the fence line in hundreds of yards of fence line. There was no other place in the park in which to find any more real estate for the path. When I explained to the RD that the restriction placed on the route would cause the start and finish to be apart rather than contiguous, she practically threw a fit. No explanation would cut it with her. The start and finish HAD to be contiguous. I then had two choices: 1)Measure some non intuitive, difficult to describe and hard to record diagonal cut across the establish park path to cut out the extra ~ 60 feet; or 2) Tell her I figured out an adjustment elsewhere that would tie the start and finish together and just leave the course 60 feet long.
I chose the latter.