“If fully carried out, a major expansion of Cuba’s private sector will benefit many thousands of Cuban families and give Cuban-Americans opportunities through remittances to help relatives in Cuba who will be working on their own,” Philip Peters, who follows economic matters in Cuba for the security- and free-market-oriented Lexington Institute in Arlington, Va., wrote in a post on his blog, the Cuban Triangle, on Thursday.

Ted Henken, a professor at Baruch College who studies private enterprise in Cuba, epitomizes the ambivalence with which prudent Cuba-watchers are assessing the latest news. He said he was thrilled by it, but was hedging his bets on how transformative the change would be.

“This is the beginning of what we’ve all been waiting for,” he said. “It’s a major change in the way the Cuban economic system will work. It will be felt by every Cuban.” But, he added, “they still want to maintain state control. We’ll see how this plays out.”

The real test of Cuba’s latest experiment will be in how it is implemented and whether work will have a correlation with wealth, Professor Henken and other experts said. Under previous privatization campaigns, he said, “people were so hobbled by regulations that self-employment was rife with illegality and corruption because that’s the only way people could make their businesses float.”

They also had to keep wary, as all Cubans do, of the secret police, given the regime’s attitude toward private property and enterprise in general. Yoani Sánchez, a dissident Cuban blogger, cited this when she wrote the other day: “Under the strict canons of the socialist economy — planned, centralized and subsidized — self-employment has always been seen as an undesirable species of pest that periodically needs to be abated and occasionally even exterminated.”

The result has been the development of a singularly Cuban style of being enterprising — somewhere between furtive and legitimate, with the real object being to simply get along. Ms. Sánchez described one man who runs a restaurant in his house and had outlawed items on his menu. He tried to persuade his daughter to marry a top chef, the blogger wrote, to get around a rule that employees must be family members.

Earlier this month, when Jeffrey Goldberg interviewed Fidel Castro for The Atlantic magazine, one comment — hinting that the Cuban system wasn’t working for Cubans any more — drew the most attention. The former president later said that he had been misinterpreted, but within days came the announcement of the layoffs and the opening toward private employment.