now i know why the announcer needed to go over the charles

Yesterdy, on FOX, I watched the Yankees clinch the AL East plus the pregame show. (I just missed right around 2 for about 5 minutes.)
The thing is, I didn't realize why. I thought all the Yankees had won was a place in the playoffs if the Indians had lost.
During the pregame show, they put something like this on the screen:

NYY wins, CLE loses: NYY clinches AL East
BOS wins, CLE loses: BOS clinches playoffs

I didn't get it from the start. Weren't the Yankees and Red Sox tied? So then why would the result be different. I tried to calculate it in my head myself, and I came to the conclusion that the bit about the Yankees must be wrong. They were in the same positions as the Red Sox. Besides, what difference would Cleveland make to the winner of the AL east? (I still don't understand that.)
Anyway, I just went on watching the game thinking that. In the beginning, the announcer said they needed someone to come over the river from MIT. (MIT and Fenway are opposite each other on the Charles River.) I thought they were just exaggerating. I was wrong.
I was surprised as hell at the end when everyone started celebrating Joe Torre's 8th AL East title.
Here's where I went wrong: Shane and I were discussing all the different crazy possibilites on Wednesday afternoon. I joked that I should have wrote a prorgram to calculate them; I should have, but it would have been wrong anyway. Shane told me that a guy from the Yanks and a guy from the Sox met at MLB HQ to flip a coin deciding where the playoff game on Monday would have been. I thought this game would happen if the Yankees and the Red Sox were tied.
But there is an obscure rule (obscure simply because its so rare that a division is tied), that states that if there is a tie between two teams, then the one with the better record against the other wins. If that is also tied, then that is the only reason why they'd need to play the Monday game.
The New York Times explained it to me well in a very short article in Section 8, Page 3, apropriately entitled, "Wny the Yankees Clinched the East."
So even if Boston wins today, the Yankees will still have a better recored vs. the Red Sox.
(I still want the us to win Cleveland to win; we have bad luck when meeting the Red Sox in the ALCS. That would cause a playoff between the two tomorrow at Fenway.)
Wait, actually I lie. I wanted the White Sox to win yesterday, thinking that the Yankees were in the same boat as the Sox, and that the white sock winning and the red losing would guarantee our spot in the playoffs. I still don't understand why the FOX pregame said that Cleveland had to lose for the Yankees to clinch the AL East. Either a typo or another obscure rule...

Anyway, I congratulate the Yankees on their triumph over the Red Sox yet agian in winninng the AL East, and wish them better luck in the playoffs this year. I actually just want to make sure the Yankees will win a World Series before 2086.