Firstly, I appreciate your producing a rational argument that...

Firstly, I appreciate your producing a rational argument that can be debated in good faith. My initial reaction is to dispute your assumption about the effect of inflation and currency changes on costs. With the lower exchange rate, local costs become cheaper in US dollar terms, not more expensive. Electricity costs, for example reflect the local gas price which is based on long term contracts not affected by overseas markets and wages are local. In terms of construction it’s pretty capital light - steel,piping,electrical only comes to about $50 million, and local products and wages are reduced in US dollar terms.
My understanding is that the original capital costs and c3 costs is considered to be intact ( I have wondered if there is a little sleight of hand here, as they have guided that there is an extra 2 years of the oxide phase and this might allow for reducing D&A and interest costs per pound offsetting a probable doubling of interest rate on debt ).
Interested in what others think.