All good points, Bob. I can imagine this topic has been discussed on this forum previously, but I have not seen the transcript. If Kevin is like me, he sometimes finds himself performing post-cal far from the course, at a time of day when temperatures are lower than during the measurement. When the difference is large, as it can be especially in spring and fall, the post-cal numbers tend to skew the measurement. In my experience, the skew can be non-trivial. In fact, I feel it can be excessive. Therefore, as you advocate, using the average constant to determine the final measurement can ameliorate exaggeration in the "long" direction.
The thing about our protocol that concerns me is that I sometimes find myself measuring far away from any cal course, with little or no time or feasibility of creating a new cal course, on a day when the post-cal temperature is several degrees F or more lower than the average temperature during the measurement. If Kevin is experiencing a similar set of circumstances, he can find the post-cal count so much higher than the working constant that even using the average constant requires lengthening the course as measured. What then? Travel back to the course to extend the start, finish, or turn around points?
In my view, this situation can create an artificial and unnecessary lengthening of an accurate measurement when the temperature difference is significant. I always compare the temperature range from the start, mid-point, and end of measuring and then calculate an average measuring temperature. When the post-cal temp is lower, I always use the average constant. What about a situation in which the post-cal temperature is 15 or 20 degrees F lower than this average? Aren't we artificially lengthening the course with the use of either the larger constant or the average constant? Should this artifact then cause us to turn around and drive for an hour or two to re-mark the course?
As an extreme example, which I can guess many of us may have encountered in a summer measurement, I once barely finished a measurement before a thunderstorm blew in. The cal course was less than a mile away from the race start/finish, but there was no alternative to sitting out the high winds, rain, and lightning before venturing out for post-cal. The average measurement temperature was in the low 90s F. By the time of post-cal, the post-storm temperature was 70F. The state certifier I was working with at the time allowed me to use the pre-cal number, which, after all, was at the low end of the average measuring temperature. Otherwise, the 8K course would have been needlessly (and inaccurately in my view) lengthened due to nothing more than a summer storm.
