For a given distance of travel, your fuel consumption can be calculated by running hours instead of distance. This is common when you're traveling by boat for instance. You don't typically say "I have enough fuel to travel 10 miles" instead you would say "I have enough fuel to run for 1 hour".
So here's my question. In a hypothetical light-speed spaceship, what would your consumption look like? For instance if you, as the passenger were riding for one year at light speed, and your rocket consumed 10,000 speed crystals (sc) in order to achieve this your fuel efficiency would be 10,000 speed crystals/year or about 1.14sc/hour.
What would the outside observers be able to say about your efficiency? Assuming the earth bound observer ages 7.2 years, would they observe an efficiency of 10Ksc/7.2 years or about 0.15sc/hour?
Whether you observe from inside or outside the spaceship, the consumption would be 10,000sc/light-year. But which "efficiency rating" is correct?