Nah. He could have stood in front of him and pretended he was going to sucker punch him in the gut, stopping his fist just short....close enough for the silver guy to fear for his safety and it would have been just as serious, if not moreso, given the nature of the threat.
It is important to understand the definition of assault. The man in the video was both committing assault AND battery against the silver man because he actually did touch him. However, if he dude had done as I described above,
THAT too would have been assault, but not battery.
http://legal-dictionary.thefreedictionary.com/assault