It was definitely a humbling experience waking up this morning realizing that all I had done was put in one 70-mile day and he was on day 17 of his journey. I had to do a little warm-up prior to him exiting the RV to make sure I could keep up with my stiff legs!
I'm not sure if he will change strategies later in the trans-con but as of right now I don't think he's listened to any music/had headphones in at all during the run. Obviously he has his little inside jokes/funny sayings that every ultra runner can catch themselves creating during a long run but mostly it's just head up and grinding out the miles.
I definitely wouldn't say he is "regretting the decision". Obviously when you are plugging away the miles the magnitude of what you are doing is always kind of lurking in the background. That said, I would say he is still mentally very strong. Throughout yesterday or today there wasn't even a fleeting moment when I thought there was a crack mentally or physically.
I think the zero day can be 100% attributed to some leg/ankle swelling and pain that they described in the Facebook post. Additionally, I think the crew was 1) semi-surprised that Pete made the decision to take a 0 day and 2) blown away when he woke up the next day and threw down 70+ miles. Shocking enough there is no residual pain or flare-ups. Just kind of weird and I think speaks to your next question--about the biggest risk to breaking the record--you just never know when something might flare up--regardless of the preventative measures you take.
Honestly, I really do think he can break the record. That said, way too many days left to identify the biggest risk. Fact is, anything could happen. He could take a wrong step on a thin road-side shoulder and roll an ankle. There are just so many variables at play with a trans-con.
Pete is originally from Iowa and currently lives/works in Nebraska. I think (and hope) he's going to have a ton of support when he goes through those states. Look at the guys background; a Badwater course record and 163 miles on a high school track. The guy eats up boring, monotonous miles. It will be fun to see what he does once he hits flat, straight miles ;)
The crew are complete rock stars. I can not stress enough how amazing and important they are to his attempt. Everyone is on-board with doing everything they can to help Pete. Watching his crew is something else.