Ohio State’s very own Dr. E.O. McLean used the BCSR concept for a long time.  Many attended his final presentation at ASA where he told a packed room that it didn’t work (summer ASA meeting in Washington DC, in the early 80’s).  How hard that must have been, nobody can imagine. 

https://dl.sciencesocieties.org/publications/aj/abstracts/75/4/AJ0750040635

http://kb.osu.edu/dspace/bitstream/handle/1811/22614/V079N3_114.pdf;jsessionid=FD47AA10B434EB512B2AD2B293C7E21D?sequence=1

https://dl.sciencesocieties.org/publications/sssaj/abstracts/36/6/SS0360060927

file:///C:/Users/billraun/Downloads/sssaj-36-6-SS0360060927.pdf

In my advanced soil fertility class (MS and PHD) I still teach the BCSR.  Although flawed, it was something that did work, but on higher OM soils where Dr. McLean studied under FE Bear (Rutgers).

Sure it did not work, but he did try.  Not sure what this all means, but as a concept, something for our graduate students, it is surprisingly valuable.