I would like to hear the opinion of an air defender as to whether a CAS would actually make their lives safer. The system eventually fitted to GR4 was an off the shelf civil system designed for straight and level, single aircraft. Fitted to a fast jet manoeuvring hard and deliberately flying close to other aircraft in the formation it alarmed a lot. And as we know, learning to ignore such warnings is a bad thing. At least, however, the GR4 did not often deliberately fly intercept courses as AD aircraft do. Could it be that one more voice bitching in your ear might actually reduce safety?