Oh, Wall Street. Will you ever learn? Embarrassing emails have been the fuel of the post-financial crisis fury. Goldman exec Thomas Montag described one of the bank’s mortgage transactions as “one S—- deal,” an indiscretion that raised questions about Goldman working against its own clients. (Perhaps missing the point, Goldman since has implemented a ban on profanity in company emails.) But you can’t stamp out indiscretion. Now we have the “goat poo” email. J.P. Morgan Chase, in a lawsuit against Lehman, cited emails it says suggest Lehman knowingly misled J.P. Morgan into keeping “goat poo” securities, reported Deal Journal colleague Joseph Checkler.