Second, if you think you were clueless, but that the regulators had a handle on it, remember: Going into the meltdown, Tim Geithner was running the New York Federal Reserve and he didn't know, either. Whose fault was that? This is unanswered by the book. But it sure didn't help that some of the biggest and most important scofflaws in the book, like Richard Fuld, who built and rain Lehman Brothers into the ground, served on the bank board.

Third, look at the eventual consequences of that period. Coming out of the Great Recession, many of these bankers belonged in handcuffs -- and I say "belonged" because the statute of limitations has sadly run out on these ne'erdowells. Yet we know these bankers' actions were so egregious that the government, led by Geithner, had no choice but to put the whole system in handcuffs, via the aptly named "stress test" regimen that now prevails.

>>Read more: Fannie and Freddie Accounting Disaster Here to Stay

Put simply, I know now that banks are far more enslaved and straitjacketed than I had realized. The ability for them to earn a real return on anything other than fees and conservative lending may be gone for the foreseeable future -- the only real punishment meted out from the era. Given the boneheaded mistakes that have been made since the crisis, like the London Whale at JPMorgan Chase (JPM) or the $4 billion error just discovered in Bank of America's bond portfolio, I don't expect the rules to change any time soon.

The bottom line? The demons of the past haunt this group far more than we realize, and when you read Stress Test you might want to thank Geithner for recognizing that someone had to check the greed, or at least grade it and flunk those institutions that just don't get that the world has changed. Unfortunately, the whole class gets held back because of the errors of a few -- hence why the group is just such a terrible place to put your investment dollars.

At the time of publication, Action Alerts PLUS, which Cramer co-manages as a charitable trust, was long JPM and BAC.

Editor's Note: This article was originally published at 8:04 a.m. EST on Real Money on May 14.

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