The model is a snapshot in time and assumes that there are no swing voters. A voter may vote for one declared party in the primary and different in the general election. There have been instances where a group packed the other party’s primary to get a weak candidate nominated. Districts are just best guesses at the time, especially if there is a lot of migration. I really like your term “political philosopher,” meaning that you can step back and analyze the situation without getting too emotionally involved. I tend to base my analyses on mathematical logic, which has nothing to do with numbers.