Question on Responsibility and the Single Executive

As I read Federalist Paper #70, I wondered whether our government today follows Hamilton's plan. He wrote, "one of the weightiest objections to a plurality in the executive...is that it tends to conceal faults and destroy responsibility." Having a single executive eliminates the "difficulty of detection" problem when something goes wrong in the executive office. Today, however, the increased size and number of departments and agencies seem to create the problem that the Founders tried to avoid by having a single executive. The complexity of the system makes it more difficult to determine who is really responsible for various issues. Although the president receives blame or praise for nearly everything that affects American citizens and is indeed responsible for the executive branch, I wonder whether the size of this branch of government could potentially allow a president to escape responsibility? Or perhaps it prevents us from holding others accountable who should be.