I just finished doing a preliminary ride of a 5 mile loop.
The course came out to 4.99957 miles. Needed a 2.3 foot adjustment. This was a slight pain, as the race director preferred a common setup point for his start/finish line. Still, it was closer than I have ever seen an unknown closed loop to come out.
I had used larger constant in my measurement. When calculated by average constant the length came out to 5.00147 miles.
I left the route as is with no adjustment. Of course, if my second ride beats the first by 8 feet or more I may have to rethink.
Sometimes the option to use the average constant can be handy.
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