Who said a week had to be seven days--or even 14?

The latest casualty of the Great Recession appears to be the calendar, or at least the one used for restaurant promotions. A week once meant seven days, no exceptions. Now that timeframe can extend to more than a month if we’re talking about Restaurant Weeks, the campaigns where a location’s fine-dining places simultaneously offer multi-course meals for the same bargain price.

In New York City, birthplace of the promotion, “week” was first redefined this winter as two partial weeks—six days in mid-January, followed by a regular Saturday night, then reinstituted for the next five days. It’s a model that’s been widely copied.

But with conditions being what they are, restaurants in New York decided to extend the cooperative promotion—for four more weeks.

The city’s restaurant trade was hardly alone in trying to squeeze a few more bookings out of the promotion. Philadelphia, Baltimore, Denver, San Diego and Los Angeles all extended their timeframes, to name just a few of the places that offer a Restaurant Week.

And I really, really mean those are just a small sampling. Another cultural side effect of the financial meltdown is the spread of the Restaurant Week concept to every nook and cranny where you’ll find a fork and a menu. Ohio’s Miami Valley has a Restaurant Week. So does Norfolk, VA, and Bethesday, MD. They, by the way, all extended their Restaurant Week by at least a…well, a week. As it used to be defined.

Floral Park hasn’t yet lengthened its Restaurant Week. This year marks the first time the promotion has been adopted by the little-known town in New York’s borough of Queens. Floral Park Restaurant Week is in addition to the Queens Restaurant Week that was held late last year.

This year also marks the first Restaurant Week for Orange County, Calif., the restaurant-rich expanse south of Los Angeles.

It’s not as if the proliferation of Restaurant Weeks is watering down their appeal. Denver’s roster of participating places reportedly swelled this year to a record 225 establishments, from 174 in 2008. The Chicago Tribune reported that 130 restaurants are participating in the Windy City’s Restaurant Week, compared with 35 places last year.

Skeptics say a Restaurant Week is nothing more than dressed-up discounting. I’m not sure why that bothers them. By all accounts, the tactic appears to work.

Value menus, varied portion sizes, bundled meals and out-and-out price chopping have become the standard marketing tools for casual-dining and fast-food chains in the current environment. Upper-scale restaurants seem to have found their Vise-Grip in the form of Restaurant Week.