Switching costs would be very high. Just consider this library. There is no standard way to handle units in C++. This presumably means that every single piece o

Switching costs would be very high. Just consider this library. There is no standard way to handle units in C++. This presumably means that every single piece of C++ software that was ad-hoc programmed to work in customary units needs modification, or some sort of shim/interface layer to become 'metric'. Or be saddled with decades of dual-systeming. As many of the examples point out, the very act of switching systems can cause problems (the Air Canada flight is the classic example). This is not to say that switching is a hopeless cause, but it's certainly not a cheap or easy task to perform. Maybe we can leverage Y2K38 as a breakpoint to help this transition along =P