Water Runway
Ditching on the Hudson leaves a lot more leeway in energy management than landing almost anywhere else in the state New York. It gives you a runway hundreds or thousands of feet wide and miles long. It's just the touchdown that's really tricky, huh? Compared to attempting a landing deadstick at an airport or on a levee, it leaves lots more accommodation of variables that might occur on the way down, such as flap/slat deployment. It certainly had to be the correct decision in this instance.
Fact as reported: Flight crew did not hit the ditch switch.
Fact as reported: FA did not know they were ditching until they were on the water.
Those are lessons learned, to be added to training curriculum, no doubt, and possibly addition of circuitry to the Ditch Switch, to automatically warn CC of impending ditching. Or, seeing the belly damage, they might just do away with the Ditch Switch.
GB