If you want a laugh, get an airline executive in front of a TV camera and show him a graph of crude oil prices since 2000.

Then draw a pretty line on the graph showing how his airline's YQ has increased over the same time period.

Then ask him to explain it.

If we must have YQ, why not ask all airlines to sign up to a scheme where the level is set by an independent body, directly related to crude oil prices? Any given route would have the same YQ irrespective of airline. Of course the airlines woudl never agree to it. I can't imagine why.