I'm amazed at the ignorance and persistence of some people. Anyone who played a dual-wielding class on Live and wasn't mentally handicapped could plainly see with their own eyes that your weapons swung independently of each other unless they had the same delay. It was a myth and a misconception in line with the belief that damage bonuses were native to the weapon rather than the character, which is why you'll find old posts on Allakhazam of people arguing that "no dude, my SSoY has 5 damage bonus!" and shit like that.
Are you seriously suggesting that using a Jade Mace in primary would make an off-hand Wurmslayer a 25/18 weapon, a ratio not otherwise seen until like seven or eight expansions later? Are you incapable of basic reasoning? Did you actually play a dual-wielding class for any length of time and fail to detect that your attacks would not be synchronized? Basic understanding of game mechanic rules out your belief, including the one where your main-hand delay would affect the proc rate of your off-hand weapon - procs aren't related to attack speed at all.
That isn't even remotely relevant to the discussion. The guy was testing the threat generation of individual weapon swings and the distinction between damage done and number of swings in regard to aggro. The person doing the study doesn't even dual-wield.