Mark, thanks. This confirms what I thought. Of course, I am not bemoaning anything. But I have talked to competitive runners in my region who do. In my conversations, many of them seem to think they are always running longer than the stated distance, even though some of them are savvy enough to run all the tangents.
Because I conduct and time races, I want to have all my ducks lined up when athletes question me about the race distance. GPS device wearers are one class of questioners. I am prepared to handle any questions from them. I want to be able to authoritatively and concisely explain what is really happening with certification measurements to competitive athletes when they ask. This discussion is helping me get there. Thanks.