Surely in sometime, someone, somwhere, had a trend setting move had to come up with the domino effect for all crosstown matchups scheduled match.

Because the crosstown or intrastate games would make for the best rivalries. You always want your biggest rival to be the last game, because you will be most prepared, and it may save an otherwise disappointing season. You also have the entire off season for bragging rights and recruiting.

A long time ago.