You bet having both systems is bad. Do you remember the failed Martian probe landing. Well Lockheed Engineers did all the Telemetry to determine speed of decent to the surface in metrics and the NASA Engineers went back and used the numbers as SAE feet and the lander smashed into the Martian surface. A 300 million dollar mistakewhipster24 said:The worst thing is when you have both systems in used on the same piece of machinery. That is just plain annoying.