That would never make sense. Someone stated this a while back, to which I agree: Starters are Fire, Water and Grass in order to help introduce pokemon to newer players. It's pretty intuitive that water douses fire, fire burns grass and grass absorbs water. Some of the others make sense (electric on flying), some take a little thought (bug being a common fear, so bug on psychic), and some making little sense at all (grass rock? ice dragon? Maybe I'm missing some things, but...). As people play they begin to learn, but to start out with fighting/psychic/dark... Those types aren't intuitive. They are later game power types which would possibly kill in the beginning, and new players would pick up on it but much less easily with such an obscure type triangle. Plus, with psychic not effecting dark, that would make things much more difficult for those with the psychic starter playing against someone with the dark one.