Stefan, your advice is spectacular. It hadn't even occurred to me that this might be what people are seeing. This is a great reminder of how useful the visualizations in the Duke will be to troubleshooting.
If this is the failure, then it should be preceded by excessive battery charging current and the "Battery Charge" amber annunciator. I would have to double check how I implemented this, but I don't believe the battery overheating should preclude normal operation of the other buses, though. This means that using the bus tie switch to manually connect the left and right buses to the triple-fed bus should still work. Also, if you wanted to check for this failure, you can check the state of "L:var_batteryDisconnect".
Excellent thinking Stefan, and thinks for chiming in!