Not at the elite world level. But at lower levels, it has actually been going on for decades. Here is something recent, ITF players and WTF players competing at an international event in South Korea designed for foreigners participation.
http://www.koreatimes.co.kr/www/news/sports/2011/04/136_68480.html Then we have a gesture by CISM Taekwondo, the World Military's Taekwondo governing authority, where they agreed to attempt an integration of ITF forms into CISM Taekwondo World Championships. This almost happened, until North Korea's United Front Department Directive and Propaganda, ONCE AGAIN, got in the way and shot all the progress down.
How so? In a very recently published article, the key member of the ITF's so-called merger committee, Ri Yong Son - who was shaking hands with Dae Soon Lee of South Korea in a photo, violated his signed agreement. Let's look at Executive Director General of the ITF Ri Yong Son's statements about the WTF, whom he claims he wants to work with, to the British media.
"Olympic taekwondo is not taekwondo," said Ri Yong Son, chief director of
the International Taekwondo Federation. "There is no understanding of the
martial arts philosophy."
"They never punch," he said of Olympic taekwondo players. "That is not a
good way to fight."
This is the same Ri Yong Son who shows up at "integration talks" with the WTF, signs and agreement that each party will respect the other, is asked by the WTF to present documents to move forward with the integration of ITF sparring and forms into WTF events. While the WTF is waiting, for 5 years now, the ITF Integration Committee director repeated the North Korean propaganda to the media.
Now this latest news, just a day ago:
CISM
The ITF Will Not Be Part of the World Military Championships
The information was given by the WTF to masTaekwondo.com this Friday morning (Seoul time), and they informed that during the CISM World Military Taekwondo Championships, the ITF Poomsaes will not be present.
So, I don't think so.