noynac, you may well have hit the jack-pot.
I played around with the Halt command and the Reboot command:
on my configuration (!... careful here)
- that I take off completely "Shut down via gdm." or not does not do anything;
- what does the trick is that I save the modification.
In a same session of Login Windows opened, I deleted the "...", save, then put it back again and save: shut-down was like in the good old days, with the normal progress bar and no garbage.
Checking with the "quiet splash" option taken off in the grub menu so that I can see what goes on, I only got "System is restarting please wait": (I was on reboot) nothing else, nothing about the network manager etc... So it does the trick... Everything shut-down nicely, at least on my machine.
The problem is that I cannot keep changing the halt and reboot command at each session. But that way be be a "tilt" for someone who knows???