At the end of our discussion on Vidalia’s Restaurant Week menu, owner Jeffrey Buben told Y&H about an experiment he conducted during last summer’s promotion, which offers some evidence that the bi-annual RW event isn’t as beneficial to restaurants as Open Table would like us to believe.

Open Table conducted a survey in 2007, which revealed that 92 percent of diners said they would return to the restaurant they just tried for the first time during RW. Now that stat, all by itself, doesn’t tell you much because it’s based only on an oral commitment. But Lynne Breaux, president of the Restaurant Association Metropolitan Washington, tells Y&H that 61 percent of diners actually return to the restaurant they try for the first time during RW. That’s according to the same 2007 survey, Breaux says, which presumably is based only on Open Table users.

Still, that’s some impressive return on a restaurant’s RW investment. Except maybe the return isn’t that great. Buben told me an anecdote about last summer’s Restaurant Week, in which Vidalia staffers handed out 2,000 gift certificates that entitled diners to take 50 percent off a bottle of wine when they returned to the downtown institution.

“There were no strings attached,” Buben says. The diners could have simply come into the bar at Vidalia, ordered a bottle at half price, and happily downed it without being forced to purchase anything else.

So how many coupons came back to Vidalia?

Forty, Buben says.

When I related this anecdote to Breaux, she had a reasonable response. “Part of that could be D.C.’s ADD,” she says. “They could be losing [the gift certificates]. You know how people can be.”