The use case I'm looking at is SmartEject plugin searches.
SmartEject runs 3 configurable searches: 1) look for duplicates, 2) books on device not in library and 3) books in library not on device.
If I can include device name in the search, I can customize the searches differently for different devices with search logic. I, personally, don't care about remember what's on which device when not connected.
I assume, perhaps incorrectly, that compurandom brought this up for the same reason: they asked for device specific searches
in the SmartEject thread.
Regardless, I think it is something I'd use myself.
Can I have a hint on how I'd get device manager/info in a custom template function? The only way I know now is self.gui.device_manager in a plugin.