Following the Hudson from Albany to NYC on a CAVU days is maybe the easiest thing a pilot could ever do. And I strongly suspect they chose a CAVU day precisely because it would have the greatest influence (Live AM TV coverage) politically.
Actually hitting the target at that speed? They could have practiced a few hundred times on FS. They probably had secondary targets chosen in case of a go-around, which is likely the case at the Pentagon.
And as the photos show, healthy turbine discs do not disintegrate on impact.