This is why I upgraded to the 5DIII . . .

Exactly. And IMO, it is NOT easier. In this case, using the center AF (if the camera is at that setting already), would be much faster, and without penalty (200/4). Also, the center AF point would be more reliable with any body, including the 5D3. On the other hand, this is just 200/4 on a static subject, a walk in the park.

Not that the 5D3 AF  system does not have its merits, it does of course. There are certainly shots that would have been impossible, or hard to get with a 5D2/5D; which the 5D3 would have nailed. But my point is that what the OP posted is not one of them.