Which doesn't give him what he wants. The B light can be on and not responsive to the switch in one of the two locations. It's Philo's initial idea, which as he figured out, doesn't work. Since he has two bulbs in the B fixture, if he can live with one bulb for each circuit, that's the only solution I see so far that does what he wants. That's the one that Gfre came up with.
In a 3-way, you get light
If you are willing to use solid state switching or "RR" series relays, there are lots of options. Otherwise you will need 2 pole switches and lots of wire. If the power is sourced in the "B" enclosure, the solution is the easiest but you are still running "4 wire" to each double pole switch to be legal in the 2014 code. (you need a neutral, even if it is just a switch loop)
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