The "who is the best coach?" discussions usually bore me. People have their "favorites" among the usual suspects. There are great coaches out here only few people know. No coach fits all but a good coach can work to fit their system to the athletes he or she coaches to get the best from them.
This blog piece reminds me of comments Bill Squires made in the 1980s about the stable of runners in the GBTC - "stallions, ponies" etc.
I hope you find the topic helpful.