Yep it is about cost base AND also being able to offer destinations to people, which is where Qantas's new offshore airline comes into things. Qantas is currently stuffed when it comes to SE Asian destinations. The demand just isn't there for wide body flights from the east of Australia to many destinations in Asia and narrow bodies which they may be able to fill if they can somehow combine people from all cities in Aus just don't quite have the legs.
The answer of course is an alliance with an airline in Asia, which Qantas has (Cathay), but unfortunatly that airline is at one extreame end of SE Asia, so is good for connections to China, with the other major airlines smack in the middle already tied up with star. This of course means anyone flying to a destination in SE Asia other than Jakarta, Singapore or Bangkok and wants to use Qantas must also fly on another airline and alliance, so of course they may as well fly that airline all the way from Oz. Hence why we have Thai and SQ in particular with so many flights out of oz and from more cities than Qantas. Indeed right now I am in Laos on a multicity trip and have already flown SQ and TG to get here simply because there is no way I could fly to where I have with Qantas or any other OneWorld airline.
So of course enter Malyasia to OneWorld thus offering a heap of new destinations to Qantas (including the two cities I started and will end my trip with) and also with Qantas wanting to set-up shop in Asia. Where the idea that Qantas want's to move its operation offshore from has me really buggered. Everything I have seen points to wanting to EXPAND offshore, not move offshore, and this includes maintenance where Qantas has shown it's commitment to continued maintenance in Aus, with some done offshore.
Qantas also has the same issue in Europe. Their major partner is at the end of the road, meaning back tracking to get to anywhere other than London or Frankfurt. In this case Qantas is under even more pressure because it has both the Asian and ME carriers to compete with, both who thanks to geography can offer one stop services to Europe. No wonder they, like most European airlines have decided to give city to city flying from Europe to Australia a miss or offer just a basic service such as what Qantas and BA are doing with their SYD/MEL to LHR services.