Yoda cannot even be considered for the worst Jedi ever he is arguably the most powerful force wielder in the known galaxy. Count dooku was a wimp compaired to Yoda as seen in episode 2 and even Darth Sidious was fairly evenly matched but in the end if Yoda didn't make his lightening explode in his face and send both of them flying then he would have won that fight. Yoda is the best and I wouldn't put anyone abouve him