Several answers on my previous question indicated that there should be ways to get around a permanent ban. While this wasn't my intention, it did raise a couple questions in my mind.
A couple comments for reference from that question:
Unless the developers/administrators of the site go to a lot of effort it is possible to get round any ban by creating new accounts, using proxies etc. - ChrisF
A permanent ban on an account is a penalty issued against an account that takes time and effort to build up. Banning against such an account can be a disciplinary measure to take away the result of that effort for a serious offense or series of offenses. - AJ Henderson
I thought there was another one too, but it seems to have been removed. That one focused creating a new account and telling others who I am.
Stack Overflow is one of many sites that lets me sign in through Google or Facebook. My assumption is that utilizing this external resource to manage my identity makes it harder to get around bans. There must be a couple restricts though, such as not having a method to register via email address alone.
Is there any data that shows this assumption is true (or false)?