I should add that sticking the wire even a little bit (six inches) out
the ends of the skeleton shield increases the current on the center
conductor...

I expect that the situation with a long wire exiting the bottom will
couple MUCH more energy into the center conductor.

So, in the context of control wires up an antenna element, the wires
coming away from the antenna and a load to represent a choke should be
included.

I'd also like to refine the shield mesh but I ran out of segments !

Dan