Obscure Michigan Stadium Query

I noticed--long before the ongoing renovations came to pass--that, on the east-sided stadium bowl rim, roughly 6-10 rows were removed sometime in the stadium's history along onstensibly 120 yards of that sideline. As some fans may have failed to notice this, I will provide a gaggle of photos for clarification. http://www.ur.umich.edu/0203/June30_03/img/030630_NewTurf-18c.jpg http://iguide.travel/photos/Ann_Arbor-5.jpg http://www.pva.org/images/content/pagebuilder/19490.jpg http://www.stubpass.com/data/news/michigan-stadium-l.jpg http://api.ning.com/files/7eyVZqyUW8ZG1I1wsX9D1MaopLpxIBGCDHrwak07qUi9f… http://bigten-online.com/michigan.jpg I imagine those sufficiently helped me communicate my point. Moving on: This "notch" in the stadium's bowl always struck me as peculiar. Firstly, it wasn't always this way. Exhibit G: http://www.djchuang.com/wp25/wp-content/uploads/2008/09/michigan-stadiu… Moreover, the new east structure finds itself conveniently engineered to complementarily fit into this "notch". Exhibits H, I: http://blog.mlive.com/jim_carty/2008/08/stadium.jpg http://1.bp.blogspot.com/_chbnMGy0IXI/SmYfSSrLE6I/AAAAAAAACwM/PiobTNm41… As for my query, I'm looking for the who, what, when, and why about this odd structural idiosyncrasy. -Was there a structural/functional reason necessitating this "notch"? -Was the "notch" created because, like I assumed earlier, ~120yards of bleachers were removed from the east side's upper rim? Or--instead--is this the result of building up the upper rim everywhere except the east side? What does the stadium's historical capacity changes have to say regarding that question (apropos a strange capacity increase or decrease)? -Who was the athletic director when this was done--when was it done?--and what was that person's reasoning? Were they being provident? I have a hard time believing any decades-ago athletic department official could have multi-decade foresight about a stadium renovation project not well defined until the first decade of the twenty-first century, but--given Yost's great foresight regarding the stadium's future--I'm not willing to rule out anything without proof. Are there any resident stadium historians or know-it-alls around to give me a hand?