Doesn't the magnet and base  have to be large enough to enclose the area you want to manipulate? I know the magnet zone has to be, but doesn't the magnet base and magnet have to be too?

"It is good to see ourselves as others see us. Try as we may, we are never
able to know ourselves fully as we are, especially the evil side of us.
This we can do only if we are not angry with our critics but will take in good
heart whatever they might have to say." - Ghandi