Why MidCos could have saved Lehman Brothers

I was struck by an article on the front page of today's Wall Street Journal which seemed to bemoan the fact that investment banks were being forced to act like, well, investment banks.  The article noted that new regulatory requirements were causing banks to shift from risk-taking endeavors into more "staid strategies" such as "trading securities for clients, processing trades, exchanging currency, managing assets and advising clients on deals and financing."  Last time I checked, these are the sorts of stable, low-risk, cash producing, midstream businesses (i.e., MidCos) that Investment Banks are supposed to pursue.  In fact, if Wall Street had focused more on its MidCos last decade vs. engaging in principal risk taking, much pain and sorrow would have been avoided.  With that, a moment of silence for my first employer...