I will actually agree with ITF Taekwondo that there are significant technical differences between kicks in various approaches to taekwondo. Differences as technically relevant as those differences between a Shotokan round kick and a muay Thai round kick. That said, I can also recognize the utility of both. And I agree wholeheartedly with PASmith when he says that the motivation behind the distinction is more to be devisive. To me, that reflects a political motivation. Not a pedagogical one. And the notion that you'd move further away from someone because they'd chosen a different political affiliation in a martial arts style is another mark of someone primarily interested in segregation. To which I say "what's the point?"