The original quote, from Duncan Bluck, is "the intelligent mis-use of aircraft", and it was the policy that built CX from a little airline to a big one. The meaning is a little different - a classic example being CX's use of the 747 on the HK-Manila route and the HK/Taipei route, many years ago. Another way of looking at it is "Don't operate thin routes" - another CX-ism, from the RB211-524 era, is "Locate a spare engine at the end of the route, and then make the most use of it by running as many planes as possible on the route."