Why does Doug use the metric system for everything but the occasional figure of speech?
Doug is a UN employee living and working in Europe since 1987, not to mention an engineer. He’s been immersed in the metric system for almost his entire adult life. The United States in Warriors’ World is still one of the last holdouts against converting completely to metric, but even so, they’re closer to it than in our world; almost everything in WW’s USA is dual-system with both Imperial and Metric measurements given together, from cola bottles to traffic signs.