Just watched the LD vs LCW match. Some of the calls were really close and it might have turned the match in one way or another. It is very strange that the chair umpire over-ruled a baseline call by the line judge as it would be hard to judge from where he is sitting. Normally they over-rule when it is a sideline shot (on his side). Thus, would badminton follow some of the other sports, tennis , being the recent one, to use the Hawk eye system. They can follow like Wimbeldon where a player,say,is only allowed 3 chanllenges per set.