I would make a huge distinction between theater improvisation and film improvisation. There isn't much improvisation in film - there's virtually none. The people that theoretically could be good at this in a theater situation don't necessarily do this in a film in a way that will work, because it's much broader on a stage. But in a movie, it has to be real, and the characters have to look entirely real because it's being done as a faux documentary, so there are even fewer actors that can do that on film.
Christopher GuestI am interested in the notion that people can become so obsessed by their world that they lose sense and awareness of how they appear to other people. They're so earnest about it. But that's true of so many things.
Christopher Guest