Thank you for raising the issue, but I'm not sure the wording you choose would be a good way to handle it. It's kind of already covered by the 1.1 no metagaming and 1.2 no hassling rule. "really good reason" is kind of subjective, and I've seen several people RP their chars as "under cover" in different factions and not sure it should be forbidden generally either (although subjectively I thought the guy doing it was being pretty lame at that moment). Although what you describe is kind of a think you see noobs do a lot so it should maybe be mentioned somehow. I'll think about it a bit more and maybe someone else has an idea for the wording.
Will add something about the ability to detect cheaters automatically as a deterrent.
