Once we were able to make a stack of tetras eight tall, and then lean it over into a long graceful arc that was reasonably stable. The end (formerly top) tetra was lower than several of the ones "higher up" (formerly "lower down") in the chain. It was very nice, but since several of the tetra apexes ("api"?) were more than 6 inches from the subordinate strucutres, it was not a legal stack. We couldn't get any more than eight to be stable enough to be self-supporting. Has anyone done any better?
<edit> and before anyone evens asks: DON'T try to do this during a competition match! Yes, if you are the red alliance and make a stack of red tetras capped by a blue tetra lean over, you might be able to change the "ownership" of the stack since the blue tetra is now lower than some red ones. But note what I said above: the stack is no longer legal, since the tetra apex is more than six inches away from the subordinate structure. Thus, you would have unstacked a previously stacked tetra, and under Rule <G18> you would then forfeit ownership of the goal for the rest of the match and the blue tetra would still be scored. So, this would be a bad idea
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-dave