I don't think that Shii Cho users are specifically weak against singular opponents, but rather that they are strong against multiple opponents. The ultra precise movements of Makashi seem to be the real weakness of the style, after all.
Kit Fisto also handily defeated General Grievous, who has stalemated powerful Jedi like Obi-Wan Kenobi, and has defeated powerful Jedi like Adi Gallia, Ki-Adi Mundi, and Shaak Ti. There was even a point where he took on four notable Jedi Knights at once and won.
Kit Fisto, one of the best lightsaber duelists in the Order's history, is also pretty impressive. This is a close fight.
Originally posted by Fated XtasyShe stale mated Malgus in there first fight and in the second she stalemated him again until he unleashed more powerful lightning than he ever did before. As far as lightsaber dueling goes Malgus never beat her
Aryn Leneer, Shii-Cho doesn't do well against a single opponent and well she dueled Malgus who defeated powerful jedi like Ven Zallow and Kao Cen Darach and survived(because he spared her life I know I know) still she's pretty impressive. that's my two cents anyway