Brian---In my opinion, and from long experience, itís an organization likely to operate in vacuum, even fail, when the Board President additionally takes on the duties of an absent Executive Director.
You are absolutely correct to suppose that there would be a lack of checks and balances in such an arrangement. And there are other consequences. Youíll no doubt see micromanaging at its worst with the President insisting on also being the staff CEO.
The President should be busy leading the board, not overseeing your staff. In the former position, the President is working with the Board to govern the organization through the development of policies, initiatives, and objectives---all toward meeting the Mission Statement. It would be a clumsy and unworkable procedure for the President to then be responsible for himself to carry out the orders and dictates of what he helped to create and foster.
You need a staff CEO, one who will, of course, participate in the formulation of policies, production of the Long-Range, Strategic Plan, and other governance matters with the Board---but the staff CEO is the one who should be charged to ensure that those initiatives are carried out. If the latter is not done effectively, the traditional Board and its President can fire the staff CEO. How can this be possible when the President is taking on both roles? This situation leads to a blurring of the line of true accountability to the donor stake holders of the organization when there is no real way to measure, reward, or punish performance.
Simply put, the staff CEO is primarily charged with the duty and responsibility to see to it that the plans and policies, as developed by the Board, are carried out.