4.2.3. An operator who, in computing its annual profit or in computing the mine-mouth output value in respect of a mine it operates, for a fiscal year, has already included or deducted an amount, directly or indirectly, is not required to again include or authorized to again deduct the amount, as the case may be, directly or indirectly, unless it is required or authorized by this Act expressly or in terms in which that requirement or authorization may necessarily be inferred.