I didn't mean to imply (and I don't believe) that all radical/separatist feminists believe that, but that the idea originated in that movement. I don't equate PIV with sex but didn't want to add jargon to what was meant to be a 101 post. Hence quotes.

Thanks for your help disambiguating.

Any time. I believe there's a high amount of nuance to the writings, activism, and ideas referred to by the phrase "radical feminist," and without noting it, it becomes very easy to get the wrong idea about the whole thing. "All sex is rape" and "all PIV is rape" are two vastly different statements in the context of this politics.