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the idea is to link/connect several keyframed layers/brushes,
so they keep their relative positions (X Y Z H P B) each together,
maybe as a MultiPlane Add-On ?

(see PS cs3 > AE "vanishing point" FX in this video podcast demo )

but Zig...before we can even think of this kind of stuff we definately first need drastic improvements in handeling & controling keys and profiles... in short... a graph editor.

I didn't mention or suggest any priority level in this request,
and I agree a Key and Profile managing improvement should be upper in the list.