[ by Larry Goldfarb ] Mike Mayo, a banking analyst known for his outspoken and combative ways, challenged JPMorgan Chase & Co Inc CEO Jamie Dimon on Friday, asking him if he had "lost a step" and whether the bank had become too big to manage in the wake of a massive trading loss. The exchange between Mayo, an analyst at CLSA, and Dimon took place during a question-and-answer session on a JPMorgan conference call discussing its latest quarterly results.  Mayo first suggested that JPMorgan's problem may be that the bank has become too big to manage.  Dimon quickly said that was not the case.  Mayo asked, "Have you lost a step? Has the focus gone off?"  Dimon grew animated as he defended the bank's track record. "Mike, this company is the same company that went through '06, '07, '08, '09, 2010, 2011," Dimon said.  "We had record earnings last year.  We had record earnings the year before.  It's likely if you look at your own estimates, we'll have record earnings this year." Mayo responded by saying that the details disclosed about the trading losses were akin to seeing how the sausage is made.  At the call, the bank reported that the loss on the position had reached $5.8 Billion. "It makes me wonder if I might get food poisoning in the future," Mayo said.  "What would you say if you're talking to a portfolio manager and you have 20 seconds to say why that won't happen again, what would you say to that portfolio manager?" Dimon, who has apologized repeatedly for the bank's mistakes relating to the trading loss, said several steps have been taken to minimize future risk. "I think it's silly for anyone in the business world to think you're not going to make mistakes," Dimon said.  "It is not possible in the real world.  I just think the mistakes should be smaller, fewer and far between, this being an exception." [Reuters, 7/13/12]