Obama’s decision unleashed a stampede to arrange and promote trips that raised concerns even among strong supporters of the people-to-people travel who feared that blatant abuses might kill the entire program.

The luxury travel firm Abercrombie & Kent quickly sold out 13 tours, at about $6,000 per person per week, after it advertised salsa dancing and rum-laced mojitos. It had to postpone the offerings after running into license problems.

Sen. Marco Rubio, R-Fl., complained the visitors were meeting with government officials and even the daughter of ruler Raúl Castro, sexologist Mariela Castro, and branded the trips as an “indoctrination of Americans.”

Rubio blocked Obama’s nominee as Assistant Secretary of State for Western Hemisphere Affairs Roberta Jacobson, until March, after what his office described in a statement as “months of negotiations with the administration in the hopes of cracking down on abuses of the people-to-people Cuba travel policy.”

Two months later, OFAC unveiled what it called “revisions” of the regulations for the people-to-people travel that effectively tightened the license application procedure and made it lengthier and more complex.

U.S. residents on people-to-people trips to Cuba were always required to travel in groups, not individually, to stick to itineraries arranged by the license holders that leave little time for tourist activities, such as visits to the island’s beaches.

The revised guidelines for license applications now require minutely detailed itineraries, and explanations of how each and every planned activity or meeting will result in “meaningful interactions” with Cubans. Even more details and justifications are required when the meetings are with government officials.

Joe Scarpaci, an emeritus professor at Virginia Tech and executive director of the Center for the Study of Cuban Culture and Economy, said his 17,000-word application for renewal of his people-to-people license was returned with a request for more details.

He re-filed it at 25,000 words, Scarpaci added, and became one of the four licensees known to have been renewed this summer.