On a standard NEC3 ECC Option A contract, if a compensation event is too certain to accurately price the Project Manager issued a set of assumptions to price to (PMA). Would it not be easier to adopt Cl 63.14, this would allow both parties to agree to actual costs incurred? At the end of the event the PM pays defined cost plus the fee to the contractor ? Both parties benefit in the instance.
Example might be importing a large amount of fill material for an earthwork project. It would be more beneficial to use actual costs incurred (Cl.63.14) rather than a forecast where one party will benefit more than the other if the amounts are not accurate.