This is factually wrong: Then you try to figure out how to configure NetworkManager from the command line. There's no tool in the entire distribution which lets you do that
Between 1998 and 2008 I always configured my networks by hand on Debian machines. Then I switched to Ubuntu for my desktop. After the first upgrade, X wouldn't start. As a result, I had no network connection, because that is set up by the NetworkManager applet (which is completely braindead: you don't need an applet to have a network connection start automatically).
Then I found there just wasn't any CLI interface to configure the network. Or at least: I didn't know which one it was. When I found out (it was network-manager-cli or something back then), it wasn't installed. Well gee, thanks, it's not like it doesn't happen regularly with Ubuntu upgrades that you get stuck on the cli...
You still don't need to configure NetworkManager to get a network connection. You can use the old methods (/etc/network/interfaces or /etc/sysconfig/network-scripts) instead.
Those are not the old methods - were they ever portable beyond debian? The old method is ifconfig. I don't care about linux any more, but on FreeBSD ifconfig still works, as it has for at least 20 years. If it becomes impossible to use KDE programs without using networkmanager, that will be a real irritation for me.
nmcli lets you configure network manager through command line http://manpages.ubuntu.com/manpages/maverick/man1/nmcli.1.ht...