Stanley Sharpey is a writer and a socialist living in London. His essay for Sublation Magazine, "The Discreet Charm of the PMC" explains the history of the term and ends up sympathizing with the Ehrenreichs given the political dilemma they faced in the 1970s.

The Discreet Charm of the PMC at Sublation Magazine
https://www.sublationmag.com/post/the-discreet-charm-of-the-pmc
Support Sublation Media
https://patreon.com/dietsoap