That brings up an interesting point David. How are most tracks laid out? Are they laid out assuming there will be a curb (.3m from the outside edge of lane 1 is 400m) or assuming there will not be a curb (.2m from the outside edge of lane 1 is 400m).
For my middle school track that I measured above, the two measurements of the loop .3m from the outside edge of lane 1 came out to 399.83m and 399.94m. The loop .2m from the outside edge of lane 1 would be 399.20m and 399.32m. There is no curb on the track.
Are all tracks laid out with the .3m offset even if no curb is installed?