I recently attended a kickboxing and MMA event here in Cocoa Florida,Don Wilson,Donnie Hair,GM of the Pai Lum System,schools from all around Florida.....Their answer;where is the real evidence for Wing Tsun/Tzun in competition?(collectively) my answer,I couldn't tell you,rules maybe? I really don't know.I noticed that in Wing Tsun publications from times past, that there were open boxing matches between Wing Tsun and other styles? Why is that?