I feel like most of the people in this thread have no idea what it actually takes to run at a high level. The fact that people think it's inconceivable to go from 12:55 to where Solinsky is now shows that you're totally clueless. The dude experienced a major injury. Missed a year. A year and a real shot at an Olympic medal. Think about the amount of running fitness he lost. He may have gotten back to being moderately in shape, but the reason he was so successful was that he was able to maintain a far higher workload for a much longer period of time because he had his nose to the grindstone for such a long time. Simple. Also, anyone who's tried to come back from close to scratch knows just how Herculean of a task it can be just to begin to feel comfortable running moderately high mileage.
I guess what I'm trying to say is cut the guy some slack. He was one of the best in the world for a year and broke an American record in what I still consider to be the most important race in the millennial revitalization of American distance running. He worked harder at this task than anyone in this thread can even imagine. To lose just about all of what he worked for... that can be hard to come back from in not only the physical sense, but also in the mental and emotional sense. He may be feeling it's time to move on to the next step. Forgive him for being human.