Well, you we refering to the cartoons, so I gave you an answer accordingly. Quite frankly, I couldn't care less about EU so I didn't read Labyrinth of Evil. I just though the cartoons were cool, but I always viewed them as just that, cartoons. Everything is a cartoon is exaggerated, ans Clone Wars is no exception.
Many characters in the series do incredible stuff, like defeating many foes, surviving high falls, jumping incredible distances, etc. But when you translate that into a movie, you obviously have to tone it down a little. That's most likely what happened with Grievous' abilities.