Back in my dads early machine shop days, he was working in a place where he saw a machinist do this very thing in an expensive manual lathe. The guy put the ground somewhere on the machine, and welded in a journal so he could machine it, and the current arc'd through the head bearings on the lathe. Trashed a perfectly good running lathe.
It was such a big deal that my dad told me that story back when I was about 8 years old, and I've never forgotten it. Some bearings are not only expensive, but a pain in the ass to change out.