First of all, I've never attended a D.E.I. course either during my business or academic pursuits.
Thus, I really don't know what I am talking about.
My initial reaction to finding myself in such a course would be, there must be a problem or the course wouldn't exist. But what if there isn't a problem, and the course simply creates a problem by its mere existence?
Some attending the course will be moved to take action against the problems which may or may not exist. Some will be offended by seeing the course as an attempt to be blamed as part of the problem. Some will see the course as a waste of time. Some will see the course as a political ploy with an agenda.
Finally as with many topics, once the subject becomes political, many will take sides depending on their tribal identity.
Do know this, glad I am white in spite of my inability to run a forty yard dash in 4.6 seconds or less.