“A president who skips half of his intelligence briefings but finds time to play more than 100 rounds of golf ... Mr. President, it is time to show up for work.”

– Ad by American Crossroads

This is from a hard-hitting ad by the right-leaning group American Crossroads, suggesting President Barack Obama is shirking his duties by concentrating on campaigning, golf and celebrity appearances. We’re going to concentrate on the first allegation – that Obama has skipped half of his intelligence briefings – since that raises interesting questions about presidential style and management.

The notion was promoted by a right-leaning research group called the Government Accountability Institute, which published a report detailing that the president’s daily calendar shows Obama receiving an in-person briefing on the Presidential Daily Brief 43.8 percent of his time in office.

Marc Thiessen, a former Bush speechwriter, then drew attention to the report in a Washington Post opinion column that is cited as the source in the American Crossroads ad.

That column includes the White House’s response – that Obama reads his PDB every day, but he does not always require an in-person briefing every day. The White House argument is that this is how Obama structured his White House operation, so it is specious to say he has “skipped” a meeting that was not scheduled.

The PDB is a highly secret document seen only by the president and a handful of other advisers.

Washington Post reporter Walter Pincus earlier this year examined how Obama has handled his morning foreign-policy discussions: “Obama reads the PDB ahead of time and comes to the morning meeting with questions. Intelligence briefers are there to answer those questions, expand on a point or raise a new issue.”

“National Intelligence Director James Clapper may be present once or twice a week, but most often one of his deputies is in attendance.”

When Pincus refers to the “morning meeting,” he is describing a regular national security meeting that is held every day at 9:30 a.m. with the president’s top advisers. In his article, he cites a meeting that took place on Jan. 13, 2012, that included discussion of the PDB with one of Clapper’s deputies. Yet the White House public schedule for that day lists no such meeting – and no PDB meeting.

So the entire controversy appears based on a semantic distinction – or perhaps inaccurate White House schedules.

Thomas Blanton, director of the National Security Archive at George Washington University in Washington, D.C., says that there have been “lots of variation in the briefing patterns” among presidents, with different consequences.

George W. Bush “wanted personal and oral, and that matched CIA’s institutional interest in face to face with the president,” Blanton said.

In contrast, Bill “Clinton the reader was known to comment that his morning papers were better than the intel brief, and better written.”