Ahhh metric V's Imperial
well the metric system is decimal and used in scientific measurements, and them god folk feared the power of arming its sheep with knowledge (science), after all how will they keep their populace subjugated if the populace know, so by keeping the metric system at bay enforced many of thier reasonings...
interestingly the metric system is based on water at room temperature, 1 mm cubic of water = 1 gram and vice versa, so the metric system is great but initially it was very hard to adopt as not everywhere is the same room temperature.