Nate needs to solve his bio-mechanical problems. Just about everyone I know who has run sustained high-mileage has had trouble with their hamstring/hip/back. Even top guys. I don't know why this should be, but if he's serious he needs to get aggressive about this problem. Among those who train hard , what separates those who run fast from those who don't is that those who do run fast don't incur or are able to fix hip/hamstring problems.
If you're reading this, Nate, you may need to try other things -even exotic things. Or, maybe you need to hit the non-exotic remedies really really hard; hit them as hard as you do your actual running. This could mean doing AIS stretching 6 hours/day. Or finding a high-quality ART therapist. Or getting rolfed....who knows? But you need to get aggressive!
I believe that anyone who trains as hard and smart as Nate does should be running under 2:10 if they stay free of injuries which limit their efficiency: yes, anyone. Nate could take even one year in which he focuses primarily on straightening out his body; he'd still be just 29 or 30.