[T2_t2]

From the article:

> If people relied on their stereotypes more or less rationally, they would rely on them to inform judgments when they had little or no definitive information, but ignore them when they had definitive information. And it turns out this is just what most people do.

So what we do with stereotypes is help us get to a better answer sans any other information, then disregard it completely when more information comes to hand. That seems like the perfect use for imperfect information.