Not really HA, but explains a lot of the troubles our company experienced when we moved into an older hi-rise office building. I remember thinking "is this guy trying to sell us a skyhook?" when a "sparkie" described how the quivering images on some of our graphics workstations were caused by an imbalanced loading on a three-phase system.
The article, "Copper Corrects Power Quality Problems in Columbus, Ohio, High-Rise Office Tower" has an obvious pro-copper theme: "Recurring Problems Vanish when Copper Replaces Aluminum Feeders." The authors were puzzled by an additional, out-of-conduit groundwire they found:
I'll bet I know why it's there. It was one of the many attempted fixes electricians made to try to correct the monitor problem we were having.
It's an interesting read, if you're into high voltage office building wiring. :-)
-- Bobby G.