"even though NSW may only be 20-30% of DTE's value"
My understanding is that NSW is considerably less than that.
Going from the figures in the 2012 Annual Report, NSW represents only 12% of the CBM 3C contingent resources and on top of that there are also shale gas resources in five countries as well.
The impact of delays in NSW has been over-estimated by many but in fact they are just a very small part of the total.