Automatic stuff sucks.
wouter@anything:~$ sudo ip link set eth0 up wouter@anything:~$ ip route show 195.144.77.32/28 dev eth0 proto kernel scope link src 195.144.77.43 wouter@anything:~$ sudo ip route add default via 195.144.77.33 RTNETLINK answers: Network is unreachable wouter@anything:~$ ip route show wouter@anything:~$ apt-get --purge remove network-manager
Yes, this really happened, and no, there were no pauses between the different commands except for the time needed for me to type them out.
Automatic stuff by itself does not suck, you should choose whether to use them or not or when to disable them. Remove nm-applet to start automatically from you (Gnome) session? network manager is one of the better latest improvements for desktop linux. Just saying it sucks because you need to do something advanced is not a fair judgement imho