Ask HN: Personality Assessments in the Workplace?

I was talking with a family member recently who told me that his company is going to be administering DISC assessments [1] as part of a human resources workshop in the near future. While he's not so concerned that these would be used directly in future promotion decisions, he does have some other concerns.

* He worries that the decision making process of the business could be short-circuited (perhaps only sub-consciously) to allow easier dismissal or acceptance of some suggestions or proposals based on the categorization of the person behind it, rather than on its own merits.

* Both of us having been raised in the households of psychologists are inclined to believe that personality inventories such as this are pseudoscientific. We're well acquainted with the Forer (or Barnum) Effect [2] and are not very willing to trust anything based entirely on self-evaluation of 45 or so questions.

* Even so, he feels that it's the psychological equivalent of being asked to drop trou in front of one's coworkers and is understandably uncomfortable about that.

* He seems to be the only one that has severe problems with this. Everyone else seems to be embracing it or at least accepting it as something that you just have to do. The later option feels intellectually dishonest to him, given the objections above.

Management is selling this as something that will enable better communication since people will be able to craft their interactions based on the other person's type. I've recommended that he ask for concrete examples of how they would tell him X if his type were Y vs. Z.

So, does anyone have any experience with these personality assessments in the workspace (or even specifically with DISC)? Any good recommendations for how to make these objections clear without becoming a pariah? Or are these concerns exaggerated somehow?

[1] http://en.wikipedia.org/wiki/DISC_assessment

[2] http://en.wikipedia.org/wiki/Forer_Effect