Not to mention, the people attached to the names are distinctive enough that you can tell who they are just by name alone. The intro is a high contender for one of the best cartoon intros of all time, simply because it tells you everything you need to know about the Eds.
ed edd n' eddy intro.mp4
Eddy's going out of his way to look cool and chases Ed after a few mishaps, establishing him as the wise-cracking schemer/dreamer. Ed knocked over Eddy and Double D and positioned the camera terribly, establishing him as the dumb Cloud-cuckoolander. Double D is shy but also very neat since he steps away from the camera, but also tries to adjust it when Ed messes it up, establishing him as the straight man/neat freak. And if you STILL are lost (for whatever reason), each of them say their names at the end, with Double D fainting at the end, further emphasizing his shyness.
All this, and only 3 words of spoken dialogue in an intro. Okay, 4 if you count the "n".