March 2008 will bring $100 Billion worth of ARMS. This is far from over, housing still hasnt seen a bottom, foreclosures have not peaked and probably wont till end of 2008 early 2009.
What makes you think the big banks benefit from a stable infrastructure? Is that when most money is made, of is it when everyone is in turmoil, many (smaller) banks topple and they can pick up the pieces? Your sense of order may not be theirs...