If you happen to date a person in the theatre who takes what seems like the most unreasonable trouble over issues that seem a mere will-o-the-wisp out of some unreasoning dread of being inadequate and you want to get on with that person, this film will help you.
There is also another point of value central to the movie that is one of those things 'everyone does' that we don't see in ourselves. It is rather like the concept of transference in psychology. We all learned what that was in Psych 101 even if it didn't mean much at the time. The idea is that if you are in a position of authority, people can relate to you out of prior conflicts with authority and dependence that they experienced in their own early lives. It doesn't mean much to college sophomores because, at the time, you haven't had any experience of authority. Kaufmann is dealing in the movie with a similar and more general psychological problem. You may have a friend who you always wanted to like you more than they did. In your mind, you have cast that real person in the role of the person who thwarted your desire. The real person may have been completely unaware of your feelings and went on to have a life full of attainment and loss and never thought further about you. For you, however, they will always be that person who withheld from you want you most wanted. You don't relate to the real person, you relate to them in the part you cast them in. When this is played out among fast friends, you can even talk to them about the fact that you are doing that and agree how wrong it feels. Then you will both get up the next day and do it again. People go on like this for years. Which is why he makes his characters go on about it for years in the movie. Real life is like the legitimate theatre and not like the movies in that the performances can go on for years. In the theatre, you have to retain a good deal of distance from the 'other' you are asked to play in order to be consistently effective in making that person come to life. The performances we give in life would be much better if we observed the same strictures. In other words, you can be a better son or daughter, husband or wife by not trying to become one with the the role, but instead by being very careful to make that role come alive consistently in every performance. Living between the playacting of real life and the playacting of the theatre usually seems the worst possible deal to be had. Kaufmann lets us see that if a play were like life and ended only with death, all the discipline and art in a role are burned out. Without a lot of care, art is a far better deal than life.