I saw that same you tube vid -- very explanatory.
I think that like a in great many of these types of incidents.. a whole lot of little things each individually might not be a problem. But under these circumstances, all together caused the disaster. Had any one or two not occurred the outcome might have been very different.
I think this goes on in a great many things in life, and every now and then, it all come together at the right time and place and fails spectacularly.
its tragic that cost to learn these things is so high.
It could have just as easily been a land based disaster as well. I cannot imagine that these ducks are anything but horrible to drive on even a regular road. Long, heavy, slow, wide, very poor maneuverability, bad visibility.
my two cents.
Kevin