[forth_fool]

Given that this performance has taken place in a large, western city with a random audience, what makes anyone think that the outcome would be significantly different if you would perform it multiple times, in similar contexts, assuming the audience has no knowledge of the other instances?

The pattern seems clear to me: you have a situation in which you are "allowed", even encouraged, to do harm to a person. You are "hidden" in a crowd. The crowd starts off with harmless actions but the get more intense over time, the boundary is pushed continuously. As long as you can hide in the crowd, you cheer. But as soon as you have to answer as an individual, you turn into a coward.

Of course you might think of specific contexts, in which the outcome would be different. But in a general setting? Why should this be the case?

The performance took place in 1974, barely 30 years after the fall of the Nazi regime. Under this regime, a whole people was put in a similar situation, where the treatment and dehumanization (i.e. objectification) of specific groups (in particular, Jews) got worse over time, publicly and continuously. I think in this historical context, the performance clearly referred to that time. I don't remember the 1970's, but in the 80's and still in the 90's, WW2 and the Third Reich were very much present in the public mind and often referred to in conversation. One example is Todd Strasser's novel The Wave from 1981, which shows how an "innocent" audience is transformed into an aggressive mob. I remember that this novel, and the movies based upon it, led to discussions where some people claimed "this certainly wouldn't happen here/to us/to me/now".

I think it needs a good explanation why today, or a different crowd, would be any different.

[SAI_Peregrinus]

Not a random audience. An audience of the sort of people who go to six hour performance art shows.

[ImPostingOnHN]

describe, with stats, how the sample differs from the mean