Alberto Salazar is indubitably one of the best coaches in distance running but for other reason is the worst.
1) Cream-of-the-crop coaching: While he is able to develop is athletes, he takes them from an already elite standard. All of his athletes were already achieving success before they even began with him. His ability to improve upon that is uncanny,but who would say that another coach could do the same
2) Resources: Because of his position in Nike and his personal running history, he has access to resources that many other coaches do not. Nike is a draw for the best exercise physiologists, trainers, doctors (who will often diagnose medication based on his referrals), etc. Is this Alberto's fault? No, but he does have head-and-shoulders better resources
3) Internationally focused: While it is cool that he can coach a British athlete to gold, he seems more concerned with boosting his resume with athletes that will win. At London, it wasn't so much country allegiance, but club allegiance. It was awesome, but what about the American distance running?
4) Selfish Coaching: Many programs are very outward with their methods (successful or not). It allows for the pursuit of running excellence to be standardized. Alberto doesn't owe us anything, but he is very cryptic about his methods.
I believe him, amongst most, to be the best to coach the sport, but I believe he could offer more to the running world. I guess that's my 2 cents