Richard Vaughn, a research director at FCB, developed in 1978 an approach to advertising planning that has become known as the FCB Grid. The model suggests that there are purchase decisions where thinking is most important and others where feeling dominates in situations requiring more or less involvement.
Vaughn’s paper ”How Advertising Works: The Planning Model” published in Journal of Advertising Research in 1980 (read it here), describes four different advertising approaches suggested by the model for products in each quadrant.
The FCB Grid earned its place in advertising textbooks. At some point, it looks like FCB took out an ad to pat itself on the back.