NEW YORK (Reuters) — Alan Greenspan is causing more of a stir in retirement than he did as Fed chairman, shocking many investors with a radical make-over: irrepressible optimist turned curmudgeonly bear.Once the darling of Wall Street, many of his old buddies are now souring on Greenspan, seeing tinges of hypocrisy and opportunism in his newfound gloom.

“I’m kind of disappointed with Greenspan,” said Andrew Brenner, a market analyst at MAN Financial. “I find it unusual that he’s been talking so much.”

Making matters worse, his critics contend that many of the troubles facing the US economy — including growing tumult in the housing market — are a direct product of his prolonged policy of rock-bottom interest rates.

His outlook was not always glum. On the contrary, Greenspan always seemed to be looking at the bright side when holding the economy together was part of his job description.

This is what he had to say back in 2005 about the subprime mortgage market, where rising default rates have now sparked concern about a broader economic crisis:

“Lenders are now able to quite efficiently judge the risk posed by individual applicants and to price that risk appropriately,” he argued at the height of the housing boom.

With many of those very same lenders now declaring bankruptcy, their efficiency in measuring risk now seems a lot less sturdy — making Greenspan’s assessment seem off target.

It’s not just housing that has suddenly yanked the former central bank chief off the pedestal where he once stood. For some, the biggest beef comes from his prediction that a US recession was possible this year.

Coming at a difficult juncture for financial markets, his comments contributed to the biggest plunge in US stocks since September 11, 2001, and revived an aversion to risk from which global investors had yet to recover.

Again, this is a departure from statements near the end of his term at the Fed, when he endorsed the theory that growth was likely to slow moderately to a more sustainable pace.

“Now that he needs material for his $150,000 speeches, is he quoting studies he previously disagreed with?” asked Jim Bianco, president of research firm Bianco Research.

Pressed on the issue at a New York conference last week, Greenspan said he was surprised by the market’s reaction, adding that he would like to continue making economic predictions now that he is no longer in public office.

Some analysts have also defended his right to express whatever views he pleases.

“It’s not so much that Wall Street didn’t like that Greenspan spoke, but that some people didn’t like what he had to say,” said Marc Chandler, senior currency strategist at Brown Brothers Harriman in New York.

“But should we say everyone has freedom of speech except former chairmen of the central bank?”

His detractors say freedom of speech is not the issue. They argue that public accountability and conflict of interest are the more important matters at hand.

Part of the discontent comes from the mere quantity of Greenspan’s statements, which seem to be more plentiful than those of Ben Bernanke, his successor at the Fed.

The fact that these appearances have come as the markets are on a roller-coaster ride and as Bernanke is faced with difficult decisions about the course of monetary policy, only makes Greenspan’s constant chatter more problematic.

Ironically, his latest remarks were filled with concern that the subprime mortgage meltdown could spread to other parts of the economy. That is a far cry from the days when he used terms like “creative” and “responsible” to describe the industry.

In part, Greenspan may be making a comeback because he simply missed the attention.

“This last speech suggested he kind of liked the limelight,” said Mike Englund, chief economist at Action Economics.

But to the extent that Greenspan’s words affect the markets, potentially making it tougher for the central bank to keep the economy humming along, his loose lips could be detrimental to the country.

Or as Brenner at MAN Financial, put it: “He’s setting a very bad precedent.”