a lot of the best armor and weapons in the game are glowing. There are some that used to glow/humm but were changed. I would think that if such a thing were to happen then some no glowing armor would need to be put in thats 'thief/assassin only.' Probably a lot more trouble than its worth.

Maybe it doesnt glow like a sun, maybe it barely glows. Assassins shouldnt be able to vanish when they are carrying a boat either eh? How you gonna carry a raft and vanish, or how do you hide with your canoe? You can always RP someone who doesnt wear any glowing armor. For a thief that might suck unless you have infravision.