Just found out...the Geox shoes of which I speak so highly DO have a small metal shank (they alarmed the step-on boxes at PIT and set off the handwand at DCA, but not at RDU) but they've never alarmed any walk-through metal detector.

If you're sent to secondary, the Geoxes will probably alarm the handwand and have to be removed then. But they still don't fit the sole thickness profile, so you won't have to remove them at airports that follow TSA policy correctly, unless you're wanded in secondary screening.