I too would avoid the barging option unless funding can't be...

I too would avoid the barging option unless funding can't be secured (with reasonable conditions) for developing on Irvine itself.

Things to consider are that you have a big long life resource on Irvine so you will be developing it at some stage. In this sense every dollar you spend on Cockatoo and with barging is really thrown away.

There is the cost of the barges and the maintenance, the loading and unloading areas and machinery, there is the maintenance (and upgrading?) of the old infrastucture on Cockatoo. There is the cost of getting Cockatoo in the first place.

Your not only double handling the product but also investing in infrastructrure you will soon abandon and build again on Irvine.

Only reason I would consider is if it you can't get reasonable funding to develop Irvine in the first place. Just IMO