Since the thema was a front of the Tang Dynasty against Nanzhao, he was able to get his hands on the updated diplomatic and military documents of the two countries. He also lived in Hanoi during his first tenure; therefore he knew some first hand information of the city, such as trades, deployments, population, etc. As the Nanzhao army sacked the city for the first time, he just escaped from being captured by jumping into the Red River and swimming to the opposite bank. Then he worked under another Jie-du located at Guangzhou where he compiled the first draft of Manchu (Traditional Chinese: 蠻書; Simplified Chinese: 蛮书; pinyin: mánshū; literally means barbarous document; roughly means the book on the southern tribes). He also worked a second tenure in Hanoi where he finished the book in 862 CE. He died in Guangzhou after retirement. His book Manchu is an invaluable source of the Tang-Nanzhao relation and for anthropological research of Hmong and Vietnam during the later years of the Tang Dynasty. For instance, his eyewitness account on the siege of Hanoi was monumental.
Chuo Jiao has been around along time and "married" with many styles such as Fan Tzi or Tumbling Boxing where it has also developed a distinctly gymnastic flair.
Chuo Jiao is now identified with Fan Tzi of Tumbling Boxing so expect a few cartwheels from Zhang's competent student.
This is a "Chuo Jiao" form (the style of Chuo Jiao has been absored through the centuries into all kinds of other fists) as a component of the Zi-Wu Men.