It’s pointless to argue whether or not the 4-year clause is legally enforceable. My guess is: nobody really knows. It’s in a contract written many years ago and meanwhile laws and processes have changed; especially those around environmental issues. Four years might be adequate to put a mine into operation 30 or 40 years ago, but not now. TCK can argue that the non performance is not due to negligence or the lack of trying but due to changes in government laws and process that make it impossible, sort of a “force majeure” situation. It’s not wise to try to force an issue when the legal outcome is uncertain, and it would be unproductive to spend millions to try to clarify the issue. Besides, CUU has to wait at least 4 years to find out if that clause is met. It serves no useful purpose, especially between friendly parties, to threaten to use that clause; because invoking that clause would be like uttering a threat! JMO