I know this has probably been mentioned before, but a search didn't turn up anything in this group.
I agree that we should have at least a three dimensional array so that we can refer to a point in 3D space (at least). The nested concept actually makes some sense to me for an attribute at that point, say a composition vector. But what I don't like is that I can't (or haven't figured out how to) define the nested array on the whiteboard. It can only be defined in a program. Further, the definition has to occur one "level at a time".
Most of you know what I mean, but the attached file demonstrates.