Actually, I have read that pacman went a bit further than that (the original that is).

For example, one ghost would find the shortest path to pacman and pursue him. Another would move based on pacman and the chaser and where they are heading to try and block him off, and the other would be mostly random but away from the others and sticking mostly to that section, as pacman will need to go there eventually and he'll have his shot.

Not sure how they pulled that off back then but it's a very smart idea lol.