"I think that where I've watched a movie go wrong, it's usually because the dread committee has been interfering with it"

John Le Carre's quote is describing the innovative process of making a movie. He thinks that when a flick goes wrong, it is usually as a result of the "fear committee" interfering with it. The "fear committee" is likely describing individuals in charge of the flick's production, such as the manufacturers, directors, and also studio executives. These individuals usually have a lot of control over the creative process as well as can choose that do not constantly straighten with the initial vision of the motion picture. Le Carre is recommending that when these individuals conflict excessive, it can cause a movie going wrong. He is warning filmmakers to be skeptical of the "dread board" and to ensure that their innovative vision is not jeopardized.