I personally have heard Alberto say that his running career was cut short by too many miles and that he would not let that happen to the athletes he coaches. Now you may have a different judgment than he does about what the right number of miles is, in the short and long term, for any particular athlete.
Les wrote:
You might be thinking of someone else. Salazar did not run his mileage all that fast. He saved the hard effort for the track.
That's not what I heard from a couple of guys that trained with him for a couple of years at AW. One guy who made multiple Nationals and a couple of World Cross teams said that Salazar and Tom Beyers would just hammer the rest of the group into the ground in training, and they all probably would have done even better if they had moderated their training efforts some instead of turning most of them into races.