Thanks for answering the part of my question relating to how arbitrary is arbitrary.
But I still would like to know, if Auto Bridging is using NIC A, and then NIC A becomes disabled, and NIC B becomes enabled, if Workstation will switch automatically? If only 1 physical NIC is enabled at a time, then surely it can not be regarded as multi homed?
If it does not then I would need 2 virtual NICs on the VM, and have it switch over as well.
More complicated than I'd like.