Can anyone explain how the problem of eddy currents, addressed in the
last line of the first comment
of......https://answers.google.com/answers/main?cmd=threadview&id=162668
 
....is addressed when the inventor says "The magnet will be one of the
current neodymium rare-earth permanent magnets with an energy product
of up to 45 MGOe and a residual flux in excess of 11,000 gauss. Common
cold-rolled steel will serve as the flux guide because eddy currents
will never complete their path in that metal
(http://www.inventor1-y2k.com/newpage4.htm)"
 
 
The problem of eddy currents in the last line is: "However moving the
shield into position is going to be dampered by eddy currents.   So
the energy required to move the shield is going to be greater than
energy generated by the device."

It seems that if there are no eddy currents, this would be an
interesting phenonmena.

cold rolled steel is used because it gives you strong thin layers. By
using layers to build the core you can greatly reduce the eddy
currents, because the insulated interface between the layers of steel
prevent the electric current from flowing accorss it.
Eddy currents are reduced, but not completely illiminated as they
still flow within the thin layers. If its about making the device
(whatever its suppossed to be - it doesn't make sence to me)
efficient, the inventor may also consider using a more conductive
core, as its the power consumed by the eddy current, not the eddy
current themselves, that use up the energy. (more conductive core =
less resistance = less heat = less lost energy).