Listened to Marathon Talk Ep. 249 to hear what Rob had to say back in 2014 (half way into his marathon streak). Completely telling. Interviewer has a hard time believing what Rob is doing. Should have trusted his instinct. Crazy how a guy who didn't like running running achieved so much. Rob touts his high pain threshold and drive as the simple explanation behind his stringing marathon after marathon. As for staying injury-free, that is simple too -- it is all about having fun. Oh, and he wants to help strengthen the rules around record for most marathons in a year.
Interview starts at ~1:16:00
"but to be honest with you"
He must have said that 10 times during the interview.