Ohh, no. I’m training for the 60m-100m, I use to run the 400m. As far as training, I use to be under “sprint coaches” who trained sprinters like middle distance runners so making the jump to Charlies workouts was like night a day difference.
The 4x30 example, well, I’m well aware of these “coaching trees” and as far as I’m concerned, most of today’s coaches who have success, there knowledge or some form of it comes from CF model he developed 25+ years ago. Other coaches just find above average athletes to work with and try not to screw them up; plain and simple.