Mike-WSM
Why bother? It relates to the factors involved in trying to find particular objects on the bottom. A photomosaic map of the bottom is but a starting point. Until an item in question is recovered, it is still in Neptune's grasp.
Even after they find the recorders, prudence would say to continue recovering items that tell about critical events on the aircraft as it fell.
Suppose the recorders are destroyed by corrosion. Wouldn't you think it prudent to learn the position of the slats and THS trim actuator? Wouldn't you want to look for witness marks on a whole range of components? Wouldn't you want to see how the cockpit switches were set up? Wouldn't you like a look at the engines to determine power setting at impact?
Mr Optimisitic
One point though, the bell curve (by which I guess you mean 2-D gaussian distribution) clearly had very different dispersions in x and y to give the narrow CEP.
Actually I weasel worded my earlier statement to indicate two wingtip lights with equal geometry and mass. The ballistic CEP has equivalent scale in all directions, but there is another probability at work as well. Supposing one wing tip light retained a tab of metal that influenced its sink rate compared to the other. The uncertainty in configuration causes a second dispersion (or uncertainty) in the underwater current direction only.