- Narm: Wei has the body of an athlete, but the head of an old man. Literally.
- Science Marches On: Many of the scientific miracles of the novel's world have either become commonplace ("telecomps" are now known as "laptops") or obsolete (a supercomputer large enough to require a mountain to be hollowed out for its processors). The easily subverted barcode bracelets and scanners would more likely be replaced by an implanted microchip and GPS.
- Fridge Logic: Since society is based on a lot of predestination based on the Family's overall needs, advancement in communication tech might have stalled in favor of focusing on genetic modifications and space colonization. It hasn't occurred to anyone that the old system of bracelets and telecomps needed updating, so no one's bothered to work on them. Or those technologies have been deliberately suppressed by the ruling elite for reasons of their own.
YMMV / This Perfect Day