George,
Yes, it's certainly an interesting system. We had plenty of regular 3-wire DC Edison systems installed here, and a few of those kept going in the older parts of some towns well into the 1950s. I think a few of the very early ones were 120/240V (or thereabouts), but they were soon converted to 200/400 to 250/500V.
I wouldn't be sure whether the insurance angle would have been the same over here in England at that time, though.
Scott,
I picked up this snippet of information from a booklet published by the Science Museum in London about 30 years ago. Some time in the next few days I'll dig it out again and see if I can post some more details.
