But unfortunately for QF, much of their balance sheet shows debits and credits in US$, so there are lots of swings and roundabouts involved in the final equation.
Yes this is very true, I'd imagine DJ (as the main domestic competitor) have a much lower proportion of their revenue in US$, so in theory JohnK's comments would be more applicable to them. However, QF do have tremendous loyalty (through QFF status scheme and corporate arrangements) that probably allows them some upwards flexibility with fares that DJ would struggle with. So it is really swings and roundabouts.