CRM is excellent value, no doubt there. When it was first introduced on the North Sea, I did wonder about the necessity of having to teach people what is basically good manners, i.e. in the way they interact with their co-workers. Having seen one or two senior captains showing their disagreement on a CRM course, it makes one wonder how they were brought up. I do agree that CRM is mainly common sense, although some professional aviators do seem to be rather under-endowed in that particular sphere. As an old colleague once said, "If there's any doubt, there's NO doubt!!"
For the record, ex-military, ex Middle East (205, 212, 206) North Sea (212, S61N, AS332), IR and 13000 hours.