Lot of semantics being discussed here. In the Lear 45 incident cited the crew selected full flap well before the landing was assured, and as a result they needed to add thrust to make the runway. It was this that led to a departure from controlled flight.
Landing assured simply means that if all thrust is retarded the aircraft will be capable of gliding to a point on an unobstructed runway that provides sufficient distance within which to decelerate and stop the aircraft.