My friend told me that someone in his guild was banned due to the TP hack.
He discovered that the GM secretly joined his party (though it didn't show up on the screen that the GM is in the party and his name didnt turn blue as what should have happened if he was in a party), the proof that the GM partied with him without him knowing is that
whenever he presses the hotkeys (F1,F2,F3, etc..) for teleporting to coordinates, his character would say the commands linked to those hotkeys when in a party...
later he got disconnected and deduced that he was surely banned, and so when he relogged he really got banned.
-END OF STORY-
*What I'm trying to point here is that, be cautious and wise when using the TP hack, you never know when the GM would spy on you
So to all the users out there, be careful!