The first thing you should do is go to the Archives section of this site and read \"History Lesson\", which is about Donaldson, who preceded both of us by many years.
In the Archives you can also find \"Changing Track Speeds\", which is about the main difference in methodology between TG and Ragozin.
Best place to hear a little about the history of yours truly and Len is my opening remarks at the DRF Expo of 2004, or by doing a search on this site.