A competency model by itself has no value. Too many companies interviewed admitted that they had spent a disproportionate amount of time on developing competency frameworks but very little on their application.
As one person interviewed said, "We're very good at designing but wickedly weak at implementing". Competency frameworks have a lot of "face validity", and developing them is apparently engaging to their creators, if not fun and exciting. But all of the work in development is wasted if it not actually used in improving selection, development and other applications.