Yet part of the fun of history is endlessly litigating it!
At least part of the history behind the bio-bifurcation was that one was a fairly pure or vanilla version of course materials supplied by the Washington State Board for Community and Technical Colleges (SBCTC) – materials now hosted on Google Drive and available via the portal page at http://opencourselibrary.org/
I don’t quite recall the rationale for that split, unless it was simply to keep an unadulterated version of the course beside one that we built around different materials our professor(s) liked. We did once have a page that listed all the SBCTC-derived courses as a collection, but that was abandoned (it wasn’t a distinction that we played up nor one that the community seemed particularly interested in).
We also once had a ‘B’ variant of ARTH101, but not of MA101…that became MA005 instead, to match the numbering scheme we used for a series from Algebra through Calculus, all based on SBCTC materials…some of which are now legacy courses. The epitaph on all this would surely be: “It made sense at the time.”
For the historical record, here are the courses that derive from SBCTC materials: http://web.archive.org/web/20150905074939/http://www.saylor.org/sbctc-saylor-courses/