[identity profile] peristaltor.livejournal.com 2016-12-21 02:16 am (UTC)(link)
Could be useful for backfeeding on a limited basis, but only in some extremely controlled circumstances. (I've had a few of them on boats, where the wiring is often easy to isolate, say, between a gen set an shore power.)

[identity profile] ironphoenix.livejournal.com 2016-12-21 05:52 pm (UTC)(link)
It can be useful... it's not a very safe way to do it, though.