I had some annoyances with this. My old company had a requirement to do some annoying tasks in intervals that depended on the inverse of the number of tons of fuel used and the document controlling those tasks said just that: ‘tons’. But if you looked in the documentation behind that requirement, it was made back when we’d been involved with a European company for sourcing that fuel so that requirement was actually based on the inverse of specifically the metric tons of fuel used, not short tons. So all the math on determining the interval for doing that task had to involve converting for the metric tons of fuel used in the interval even though the newer fuel supplier we had swapped to and we ourselves were using short tons in essentially every other context. And since the controlling surface level document just said ‘tons’ without specifying which kind I was always having to correct the math of schedulers and new people on my team since they would eternally think we had more time to perform the task than we actually did and respectively plunk it down late or tell someone who was asking that it be moved that it could be pushed later than it should have been.