From NASA Spaceflight's article SpaceX Falcon 9 launches first NRO mission with NROL-76:
The NROL-76 launch was not to be targeting a sun-synchronous orbit, typically used by the NRO’s optical imaging satellites. While it is possible to reach such orbits from the Kennedy Space Center or Cape Canaveral, the rocket would have to perform a series of dogleg maneuvers that would severely limit its payload capacity.
What does this mean? Is there a diagram illustrating what these maneuvers might look like? Why a series of them instead of one, presumably longer maneuver? Has this kind of thing been done recently?
update: I have found dogleg mentioned in this blog.