IIRC, I thought there was a 'rule change' a few years ago that potentially allowed under 12's and over 75's to keep shoes and light outerwear, depending on the airport/checkpoint. I'm not sure, but I think it might have been before Pre. I think the problem was that kids and the elderly disproportionately slowed things down when they removed their shoes and then put them back on, often right at the belt. The justification, oddly enough, was that these two age groups generally represented a slightly lower risk. That's a huge departure from hearing that terrorists were known to use children and handicapped people in wheelchairs.