Arrrgh :-(
Martin Ender, whose legacy of computational regex answers played a big part in inspiring me to be active on CGCC ~5 years after my initial post, finally has some activity on CGCC after 2 years of seemingly total inactivity (or 5 years since any heavy activity)... and it's in response to me pointing out a bug in one of his Retina answers. But his response is not to fix the answer, it's to delete it :-(