Hi Henra
That was also my impression. The drift of the bodies represented a rather sharply shaped Funnel.
The close proximity of the bodies makes it less likely that they were subject to significant changes in current direction than if they had been widely separated. Changes in current direction would be likely to have produced more spread that we have seen here. Simply because changes in current will not be uniform and therefore generally act to create dispersion.
The buoy data that was posted a couple of days back does demonstrate this. Separation increased with each change of current. Admittedly these buoys were widely separated from the outset, and therefore were prone to further separation with changes in currents. It is a positive feedback thing - separation encourages further separation with changes in current because these changes are not uniform. However even closely grouped objects will disperse with changes in current.
Thus even though the bodies all entered the water at the same time and place, their close proximity through days 6 to 10 does then tend to argue against extensive changes in currents prior to discovery. Which argues for a simple rather than a complex backtracking model - although one which will inevitably produce a large circle where it is "most probable that the impact took place" rather than a single point.