Absolutely. You can completely tell the people who travel rarely (or at least, rarely since 9/11) -- they are the ones unloading their change, pagers, keys, and cigarettes into bins literally seconds before they're supposed to walk through the detectors. (Not coincidentally, they are the same ones who count their change and lace their shoes while standing at the end of the belt, unaware of the carry-on and bin back-up they are creating.)

I've learned to disassemble myself (belt, wallet, change), dumping everything into the pocket of my laptop case, while walking to the checkpoint. Once I'm in line, out pops the laptop and off slip the shoes (yes, slip on shoes are a necessity). Once you've done it a few times, it's actually pretty routine.