If I were flying over BFE Alaska, I would agree it's a good idea. Flying up and down the Willamette Valley, or even the coast range..it's a complete waist of resources.
2) Radar fallowing? Transiting Class C and B airspace it is good, Flying over boonyville at 2000ft..it doesn't help much. Besides, if you can't see it you are going to hit it, whether they tell you it's there or not. In my experience, people look outside the airplane better when they don't have someone on the ground looking for them.
Both provide a false sense of security.
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