arbitrary coherence

I started reading Daniel Ariely's Predictably Irrational, and the topic of Arbitrary Coherence was brought up. In the book's words, "Although initial prices can be "arbitrary," once those prices are established in our minds, they will shape not only present prices but also future ones (thus making them "coherent"). " With this being said, I am looking at stock prices a little more carfully with the focus being on the relationship between a company's stock price and its true value. If there is a significant difference, is arbitrary coherence a reason? Can understanding the topic of Arbitrary Coherence make a person a better investor or trader? I think so.

Comments welcome.