Where did you get your infos? Worms2D doesn't say anything about Team17-knocking, nor does WAHelp, neither does BTP. The only thing I found was one tourney in Worm Olympics and one in WO in 2006, but it sounded like the rules were "just-for-this-tourney" for me, especially cause other tourneys highlight "everything is allowed". I can't remember about anything that has to do with knocking and team17 either. I'd just like to see a source, otherwise it doesn't sound too convincing.