Interesting. I`m very very sceptical about the claim, even tho it could have happened in a lab in Alaska or something.
Find it curious that they`d add the copper to the ground line.
Good thing for me is it may make the pcbs stronger, more than anything else. I cringe when putting some hs/f on as I see the mobo bend.
.. and always forget to put a plastic bridge underneath the next time I install the mobo as I promised myself I would.