"The market's running," Darst said during the opening day of the SkyBridge Alternatives Conference in Las Vegas. "When cookies are passed, grab the cookies and realize they may not come back around again, and it's not always going to be thus."
- Is the Federal Reserve tightening monetary policy?
- Are stock price valuations stretched?
- Is investor euphoria present?
- Are bond spreads widening?
- Is there a recession looming?
- Are transportation stocks, small caps and bank stocks retreating?
"Right now we are 0-for-6 in the bear market checklist," Darst said.
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In spite of the seemingly easy path to more gains for the stock market, which is up the more than 20 percent from its last low required for a technical bull market, there is still plenty of fear in the market.
Many market experts believe that the main propulsion behind the surge has been the Fed, which is buying $85 billion in Treasurys and mortgage-backed securities each month in an effort to keep liquidity flowing.
Also, geopolitical factors continue to spark concern, particularly over a slowdown in China and another flare-up in the European debt crisis.
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This year has seen the first consistent inflows in stock-based mutual funds since the financial crisis began, but investors are still cautious and pouring just as much cash into bond funds.
"Nobody is buying stocks, and they will someday," Darst said. "There will be a coil-spring reaction."