It is good to see a post about netnews/usenet. I thought things started going to hell when HTML-encoding became a significant part of the feed. Half of a group's subscribers would plonk the sender, another half would flame the sender, and the third half would try to muddle through and treat the article as plaintext with a line break somewhere in the 70-80 character line range. That might have been the start of endless September.

The article didn't touch on the suggested way to handle authenticating control messages that reconfigure the INN groups file, it's based on PGP-signing the body of a control message along with selected and identified headers. The PGP signature was stuffed away in a header making it unobtrusive. It was fairly obscure, perhaps that's why the article missed it. The technique is described here https://ftp.isc.org/pub/pgpcontrol/README.html and an example signed control message here ftp://ftp.isc.org/pub/pgpcontrol/sample.control

I worked with NoCeM, nocem-on-spool, and the cancel moose (tm) back in the days. Applying retroactive cancels to the spool was and remains controversial.