The latest leg of the bull market in stocks could have a familiar impetus — a Federal Reserve unlikely to rock the boat, particularly while many of its members are still learning the vagaries of central banking.

With Jerome Powell about to take over as chairman and most of the seven-member Fed board of governors to be new appointees, the tendency will be toward safe decisions and away from anything likely to unsettle Wall Street, said David Rosenberg, chief economist and strategist at Gluskin Sheff.

"The bull market continues unabated and is taking on a speculative tone in the process," Rosenberg said in his daily note to clients Thursday.

Those observations came the same day as stocks set still new records as the ninth anniversary of the current bull market approaches in two months. Major indexes posted gains better than 0.5 percent in afternoon trading.

In his note, Rosenberg wondered whether the Fed will "remain a serial bubble blower."

The criticism is familiar: Through low interest rates and trillions of dollars in bond buying, the Fed has created a credit bubble of low-cost cash coursing through the economy and, more particularly, risk assets like stocks and corporate bonds.