yeah regional divisions make sense, but i'm not sure why they would matter all that much, in the grand scheme of things it's not exactly "my problem"

I wouldnt be surprised if they weren't fully separate, from what i understand though, texas has a pretty much isolated grid since that allows them to get around federal regulations for power production. And the east and west would more than likely be a systems scale thing, it's just better to have it split down the middle. Considering how few people generally live there.