Can someone explain to me how this would even work?
So you Vengeance climbs and climbs and climbs for 20 sec, and then resets? or the 20 sec is set for the duration that you vengeance can climb, and then it will sit idle at the max level it reached in the durated time?
It may have changed....but if I recall, Ghostcrawler had a post explaining Vengeance changes that stated the 20 seconds is a rolling buff. So every second it looks twenty seconds back in time and calculates how much damage came in, and then constantly updates the buff accordingly. (The "every second" but was just a number made up to explain the point...I don't know how often it actually updates it's 20 second lookback.)