As a matter of fact, it has been used in the 80s and the 90s mostly in academic circles - but that's all that is to it. Its spreading was - and is - limited to academic communication and some leftwing newspapers.
I must be living in academic circles, among left-wing people (publishers of the german-speaking Swiss dailies included

), and in a time-gap, then… Interesting, I hadn't noticed.
PS. Personally, I couldn't care less, I don't need feminine endings to express my identity, in fact I hate forced feminins if the language does not use them spontaneously, and would never use BenützerIn and such myself. I was just explaining…
