> A better test would be two inanimate objects, adjusted to neutral
buoyancy,
> released in current, in open water, where the current is most likely to
stay
> the same the longest.  They should move together until some outside force,
> like alteration in currents, affects one of them without affecting the
other
> in the same way.
>
Ah, there's the rub. Inanimate objects.  I know some inanimate people but
not many and none that are divers (tho some seem to be anchors - on the
local TV news.)

CH