Hey, psychologists! Since I know several of you, and one or two of them might actually read this blog, I have a question.

I'm taking Yet Another Management Development Class, and this one (like all the other ones I've taken) has dragged out personality classification test. This one is called DiSC (see also the Wikipedia entry), and it joins Myers-Briggs and Strengthsfinder in the roster of 'personality tests I've taken.' (Sometimes voluntarily.)

My question: do any of these tests have any sort of validity whatsoever? And is there any evidence that they actually help people develop themselves better than they would otherwise? They seem like a bunkum to me, frankly, but I'm willing and eager to hear otherwise....