I agree with Takhara... I really don't see the problem. Its no different and is no different from what i saw a swordsman doing once.. Using Magnum break around GTB because fire doesn't hurt GTB, thus killing nothing but all the Male thiefbugs... Is that exploiting the GTB's resistance?
Also, yeah, its not a glitch.
Edit due to new replies: Glad it seems to have resolved without me? xD