That said, I'm still not *quite* certain who the exact culprit is in this instance...
I know it stems from the failure to load/unload the relevant kernel modules, as that, at least, is made pretty obvious by the kernel shouting at us, but the timing is a bit iffy, and the exact error varies wildly between devices, and, as ixtab said, the network interface *sometime* does finally come up, albeit on the default IP, so I kinda stopped looking for a definitive answer and just worked-around it by never toggling with a cable plugged in
.