First, look through the Strava distance challenges to find transcon or high mileage runners. I found this guy, for example, through the April Distance Challenge(https://www.strava.com/challenges/April-2016-run-distance-challenge):
Name: Jason Romero
Route: VisionRunUSA Transcon from LA to NY from March 25, 2016, to May 23, 2016.
Talk about a completely different looking routine! This guy ran 50 miles a day every day for a couple months, but went a more southerly route (through Phoenix and Payson, AZ, which added some steep climbs). There are a couple auto segments, but they are complimented by actually runs over the same route. Fore example, this one in Twenty Nine Palms, CA:https://www.strava.com/activities/529925890
(auto, left at 5pm)https://www.strava.com/activities/529918577
(run, same route, left at 5am)
This guy actually DID run 50 miles unsupported through the California desert (although there may have been a support vehicle I suppose) but his fastest half mile was 4:03 and his fastest marathon was over 6 hours that day.
On his last day, he ran 70.3 miles, and, surprisingly, recorded his fasted 5K of the whole route: 21:17, going down Broadway in Manhattan. Looking at the GPS track there is a lot of GPS noise but he did indeed travel a bit faster here, but he's not laying down 6-minute miles for 20 and 30 miles... Anyway, I think this is what a transcon would actually look like because, well, it was one.
Btw, Andy Persson was #2 for April.