Former Massachusetts governor Mitt Romney isn’t president yet but he sure is acting like he’s already won the office.

U.S. Republican Presidential candidate Mitt Romney addresses a business roundtable with company leaders in Washington June 13, 2012. REUTERS/Jason Reed

Romney is breaking from that course somewhat this weekend, agreeing to appear on CBS’ “Face the Nation” — his first non-Fox News Channel Sunday show interview since announcing he was running for president in 2011.

Viewed broadly, what Romney is trying to do is obvious. Republicans believe — and they are almost certainly right — that if the November election is a referendum on President Obama and his handling of the economy, they win.

Why then, many in the party argue, should Romney make himself widely available to the press and, in so doing, virtually ensure that the spotlight occasionally moves off of Obama and onto him — and not in a good way.

That’s why Romney has almost exclusively done televised interviews with Fox News Channel — whose editorial bent tilts conservative — and has kept the press at arm’s length (or even further) throughout the campaign.

The latest incident? Romney’s team escorted the press out of an event in which he was taking questions from members of the Business Roundtable on Wednesday night at the Newseum in Washington. The Romney team notes that reporters were escorted out at the request of the Business Roundtable. (Worth noting: President Obama did the same thing when he spoke to the group earlier this year.) And, Romney’s last direct interaction with the people who cover him on a daily basis was two weeks ago when he did a press availability outside of the now-shuttered Solyndra plant in California.

Ed Rogers, a veteran Republican strategist, fully endorsed the Rose Garden strategy — even questioning why Romney would agree to do a Sunday show this weekend.

“What is the upside to a sunday show appearance,” asked Rogers. “Don’t do it. Things are going great.”

The problem with a Rose Garden strategy — particularly if you aren’t the current occupant of the White House — is that it has limitations.

There’s no question that 95 percent of beating an incumbent in any election is convincing people why he/she deserves to be fired. But, there is at least 5 percent of the equation in which the challenger must prove that he/she is up to the job they are seeking.

The bar a challenger must clear to be considered a credible alternative is admittedly lower than the hurdle an incumbent faces to prove to the electorate that he deserves a second term. But, the bar exists.

That’s why simply running on an “I’m not that guy” strategy isn’t likely going to be enough to get Romney into the White House. Yes, Bill Clinton’s main case in 1992 was that President George H.W. Bush was mishandling the economy. But, Clinton closed the deal only when he was able to sell the public on the notion that he had good — and better — ideas to improve things domestically.

Republicans politicians up to and including Wisconsin Gov. Scott Walker and Wisconsin Rep. Paul Ryan have suggested in recent days that Romney needs to offer his own alternative, positive vision for the country — not simply run against the vision offered by President Obama.

“Even with the economic headwinds the President is facing, and they’re at gale force with no sign of subsiding, Romney is not in the lead,” said John Weaver, a longtime political adviser to Arizona Sen. John McCain. “This is really defying political gravity. Given that Obama is over performing in some key groups, Romney needs to be more aggressive in telling his own narrative and not sit back hoping a slow recovery will do the President in.”

To date, Romney and his team have clearly benefited from their embrace of a Rose Garden strategy. But their decision to appear on “Face the Nation” this weekend also suggests they understand the strategy’s limitations when it comes to convincing voters that Romney is the right person to serve as the 45th president of the United States.