His coaching choices have not matched well to his individual circumstances. We'll never know if the kid is durable or not because Wetmore, Hudson and Salazar all fixate on mileage. Like Ritz said in an interview, he realized he'd been overtraining for years. And then of course, Alberto decided to overtrain him too, with the big bold experiment, never bothering to consider that Ritz is far far more talented and tougher than Salazar ever was. A superior racer as well.
If Ritz caps his mileage at 80/week, something closer to what Lagat trains for 12:50 (and what Rupp trained for 27:10) he makes the 2012 10000m team rather easily. US 10000m record might take him two seasons. Hard to say that 27' 10000m shape is not good preparation for a marathon since the two best marathoners in history are both <27 guys.
Lung issues are actually quite common in altitude training, especially for athletes coming up from sea-level. Moreover, it is important to understand that the work of breathing is a far bigger issue for an elite athlete than one of medium talent.
The foot and lower leg troubles are due not just to the excessive volume, but also his talent -- cardiovascular fitness outstripping the physical capacity of bones and soft tissue. Added to this is the overall negative influence of altitude on bone formation.