I think it's just that nobody has ever tried that. You're going to need
custom code for this.

It's a system field and it's very difficult to change it even with custom code.

Yeah, I figured that was the case. Thanks for answering. I really appreciate
you guys.

Definitely not a easy out of the box feature, my guess is it is a db field but
even then probably a windows Token id or SID, and not just a plain text value,
So bare minimum your looking at, either tapping into the db in an un support
Microsoft way with SQL or possibly writing some custom CAML or LINQ query.