Bypass network manager on specific SSID

[Grant Williamson <traxtopel gmail com>]

Dan,
   is there any exit code that can be included in a script placed in 
/etc/NetworkManager/dispatcher.d to bypass
NM trying to connect to a specific SSID.
i.e.
NetworkManager tries to connect to essid HELLO, instead of NM doing the 
connection, script runs wpa_supplicant manually. Or is this plain 
stupid, to ask?