Folks, what are you talking about? Kaiba "twister-ing" Dimension Gate? FYI, I tried battling Kaiba 3x with my good old Kaiba farm deck, and still NOTHING HAPPENED or better, nothing really changed? Were you trolling the people here?
Ah, for your question, why would he do that? There's noting to Econ because during my last turn, the field is always empty except for a lone D.Gate, and a set down field spell. Neither one is being destroyed nor the Gate being Twistered. You guys are definitely doing something wrong.