I got the SSSS earlier this year on a MAD-PHL flight. When leaving Europe with a U.S. carrier, one needs to go through some sort of question and answer ritual. Simple questions like if your luggage has been with you all the time, do you carry guns in your luggage, you get the drift. Since I was walking with a cane, the security guy asked me when I had surgery. I thought that was quite a silly question and replied that in the U.S. surgery is not a prerequisite to walk with a cane. I don't think he liked this answer and he left for a lengthy chat with his supervisor. When I finally was allowed to approach the check in counter, my boarding pass was printed and was marked SSSS. I don't believe that this was a random act and attribute this solely to the interaction with the security agent and certainly not to my GE status.