I think the problem is that NM just completely ignores interfaces that are configured by network-admin (or directly via /etc/networks/interfaces).
I think the correct thing would be for NM to not configure those interfaces but still watch them, so that it knows if the machine is currently connected via a wired connection in which case it should not try to use WLAN at all. When the wired connection goes down NM would notice and start searching for WLANs...
I can confirm this.
I think the problem is that NM just completely ignores interfaces that are configured by network-admin (or directly via /etc/networks/ interfaces) .
I think the correct thing would be for NM to not configure those interfaces but still watch them, so that it knows if the machine is currently connected via a wired connection in which case it should not try to use WLAN at all. When the wired connection goes down NM would notice and start searching for WLANs...