Wow, this teaching technique is not acceptable in this day and age, but pretty creative/radical in its time. The students' learning would take place at a visceral level when it is acted out--not something just learned aurally or read. Emotional learning would also take place as they experienced both sides of the role playing. It reminded me of that other famous psych experiment where participants were assigned roles of the prisoners and guards. Humans quickly take to roles of power, justifying and abusing their superiority and dehumanizing the "other." Our society is quite predictable in that way. Skin color is a very visible distinction, so we make judgements quickly and perpetuate the power dynamic in subtle and not so subtle ways. Ugh! We must consciously work against these tendencies!