re: Yale SJW's Scream At Professor for Not Denouncing Offensive Halloween Costumes

I'm curious how this all came to fruition. did she just see him on campus and call him out on the spot...was this arranged to be a public debate...it seems like only minorities care to show up and it was in a pretty central location. and the snapping thing? is this a formal/proper way to express your agreeance(yea i made that up) with a specific point being made? i don't doubt this is real, but I'm curious how it got set up... seem like it was a pre arranged function...