Perfectly valid. This particular tip certainly seems to have caused some great discussion! It worked for my particular case, but I can definitely see it not working for everyone.

I've added a link to this thread to my tip, and expanded on it a little to warn people that it's not for everyone.

Someone else pointed this out too. The goal of the tip is really to stop users SSHing in just to fix that one little thing, so you could still allow your automation frameworks SSH access and just disable it for users (the idea is to disable in firewall, not turning off SSH on your server, that way you can still use it for emergencies). The idea worked well for me, but obviously isn't for everyone, YMMV.