Designers live in fear of the committee. When working through design problems committees are often where good ideas go to die. A huge problem with groups of people needing to sign off on ideas is the fact that once an idea gets run through a bunch of people's checklist all of the things that make something unique get stripped away. Any corners get rounded and anything that yells gets hushed. In the end the design is faceless and blends into the background.
Creative endeavors that are revered often have the stamp of an individual. Great companies are often remembered for the personalities of their leaders. Apple, Google, GE, Facebook, IBM, Coca Cola, Ford... the list goes on but all of these brands at some point were led by individuals with hugely distinct styles of leadership and public perception.
Yet even at companies large and small there needs to be "buy-in" in middle management. Hence committees are formed. It is a management problem and a designers bain. But the idea of personality can help focus committees and also help generate better designs. It is sometimes not enough to have a targeted creative brief. Creative briefs no matter how targeted can be solved in a variety of ways. Perhaps along with the companies rationale the question of what kind of personality this committee or company should have needs to be asked.
You don't even have to talk in specific traits. You can speak in generalities. Are they Elvis people or Beatles people? Are they conservative or progressive? Are they Joe Friday or Monk? These things help to define the voice they want to use and are more relevant to attitudes than color and form. The right personality is the essence of a brand. And a committee doesn't have to stand in the way of that fact.