Agreed the process is very simple. The innovation that makes the resolution worth it is (as Derek also mentioned in the blog post) an efficient way to re-racemize the L-meth to DL-meth, which can then be resolved again. With steady state production and pooling this means it can be done using just one batch size (and not ever smaller "brsm" style bathces). If these steps are efficient enough you definitely get much more bang for your buck. Here is one such method[0] which probably inspired these drug manufacturers (as they use thioglycol and AIBN, which has been found in clandestine lab seizures).
[0] https://sci-hub.se/10.1021/jo061033l (published in JOC in 2006 - so only a mere 2 decades behind the curve)