Could you help me to answer this? 1) Please critically comment on the following sentence : "Weighted Average Cost of Capital (WACC) is too complicated and not useful for financial management as we should only calculate the cost of borrowing/debt since we do not have to pay our shareholders any dividends if we choose to

Could you help me to answer this?

1) Please critically comment on the following sentence : "Weighted Average Cost of Capital (WACC) is too complicated and not useful for financial management as we should only calculate the cost of borrowing/debt since we do not have to pay our shareholders any dividends if we choose to."  

2) According to a Chief Financial Officer of a listed company, she thinks that financial leverage is more effective than operating leverage in the real world as one can use financial derivatives to manage the risk accordingly. Do you agree with her?