Why?
It was carried out by a group of people who wished to learn to sing, all of them voluntarily participants.
It is a method used by many theatre schools - and it was effective enough to produce great singing and some groundbreaking research work.
Perhaps you might give an example of where it was used 'beyond the Iron Curtain' - was always told that's where they shot people.
Constructive criticism and helpful advice is far more productive than constantly being told you're great - especially when you're not!
Jim Carroll