When using the IP reservation feature of the DHCP panel, I inadvertently assigned the same hostname to a wireless interface on the same PC with a wired interface. To my surprise it seemed to work. However on closer inspection, the list of DHCP-assigned IP addresses no longer included the original interface. In other words, it appeared to allow two interfaces to have the same name, but it did not work.
Assuming that two interfaces are not permitted to have the same hostname, here is a suggested resolution: perform a check when a reservation is attempted to see if it is a duplicate name, and report it as an error, rather than proceed.