I've been one for a short while, and get to play devops from time to time. When I see a machine so broken that it can't give me a tty, it's time for a reboot (if last command caused it - actually don't remember it ever happening), full reinstall, or trash. I won't lose any time recovering it. If there's some important log on the disks or anything, mount the disk on another machine.
Now, I've recovered a broken machine plenty of times at home. I've edited files with sed and pipes because I broke every other editor available. I have never actually edited the memory with sed, but I could if I had to. But all that is at home, where it's fun to create a crazy configuration, and totally not fun to throw things away. It's fun, but completely unproductive.