Interesting training basis

I was reading up on training, and I came across a training methodology that goes like this. Take your target event, for me the 200 free. Training speeds are dictated by your times two distances lower, for me the 50 and the 100, and two distances higher, 400/500 and the 800/1000. Warm up and cool down fall outside of this. Compared to traditional training, this would be low yardage, high rest for most people. Has anyone played around with this? Using my 100 split from my 1000 as my endurance pace would be much faster than what I am currently doing. I like the concept because it gives so much guidance for training efforts, and retesting the levels is trivial. That's it, I don't have much more detail than that. I can't find the article I read this in, but apparently this is a common training method for track.