The leader of the Techno Union just pledged droids like the Trade Federation did. He wasn't a bad @$$ fighter like Grievous. The Seperatists "hired" Grievous because, according to Insider Magazine, he's programed with every known fighting style in the galaxy, including lightsaber styles. So when he fights Jedi, he recognizes what they're going to do before hand and is able to whoop on 'em. But, he doesn't have the force, so he isn't quick enough to block blaster shots. (which I find odd since he's got all this mechanical brain/calculating software, but he can't quickly figure out the tragectory and speed of a blaster bolt and deflect it. )