I don't know why I never looked into this before, but after watching him run at Millrose I was surprised to read that he's still with James Li, who coached him at UW and is now at Arizona.
As a high school coach who often sees his kids graduate and run slower in college, it has to make you wonder if one of the issues with American distance running is the lack of coaching consistency. I've wondered many times before eif the kids could still run for me for four more years that they would ru significantly faster than if they went off to college and ran for someone else. Sounds cocky, but I don't mean to come off like I am superior to high school coaches, just that I think that consistency of coaching and team environment plays a big role in a kid's success.