[ArbitraryLimits]

IMO the reason why Americans prefer Farenheit to Celsius is that the 0 and 100 points correspond to roughly the limits of common outdoor temperatures, rather than water's state changes.

Pretty much the same argument for miles per hour vs kilometers per hour - 100 mph is all anyone's ever going to go during a normal day.

That's an interesting point about being able to divide by half more than once for feet/inches, though - I hadn't thought of that before.

(From another American with a physics background)

[nfoz]

Let's face it -- people have a strong preference for whatever system they are used to. There's extremely strong inertia, and efforts to try and justify one system over the other are not especially effective.