Benny was a professional fighter and well trained to take hits. He probably agreed or might have even suggested to Jackie not to pull Jackie's punches, in order to produce the greatest visual effect. Accidents are inevitable so I'm sure Benny got hit harder than planned, but both men understood it being part of the job. The entire crew was dedicated to making a great movie and Jackie is too much a professional and perfectionist to have even thought about jeopardizing filming by starting a real feud offscreen with his main onscreen rival. What would have been Jackie's motive, to show up a professional fighter in front of everyone to prove something or was he this kind of an asshole in general? The speculated events are completely out of Jackie's professional character. This man has placed his movies and profession first and sacrificed his body for his audience his entire life. The speculations are baseless and an insult to him.