There are two parts that make up a road record: course verification and validation. The course distance is verified by measuring the course and may be completed either before or after the running event. During the running of the race, a qualified individual will observe the runners confirm or validate that the runners followed the course that was measured.
There are two Cherry Blossom 10 miles courses that were verified in the past.

The V in the status column of DC07001JS and DC10003JS indicate the course was verified. Should a mark be set on either course, that equals or betters the current American record, it would not be necessary to send a measurer out to verify the course distance. As of Jan 1, 2014, US National Championship road running events are required have the course pre-verified.
In order for the mark be credible, the original measurer or another IAAF "A" or "B" grade measurer in possession of the complete measurement data and maps must validate the course measured was the course that was run, normally by riding in the lead vehicle. (IAAF Rule 260.28d)
Hope this helps. -- Justin