While trying to dig up more context, I found https://www.b-list.org/weblog/2012/feb/13/reddit/ which linked to https://web.archive.org/web/20131231120008/http://www.shirky... (A Group Is Its Own Worst Enemy)

Navigating upward to the class syllabus also shows more of what's going on with the link itself: https://www.cc.gatech.edu/classes/AY2001/cs6470_fall/ (The Design of Online Communities by Amy Bruckman). [I think I took a video game course from her, but I'd have to dig out my transcript to say for sure]