Hold the obituary on fine dining, and pass the 12-course tasting menu, please.

It's a refrain chef Marc Vetri hopes to hear often after March 15, when his signature gem, Vetri, abandons a la carte dining altogether for $135 tasting menus, a decadent splurge previously required only on weekends.

In a move that seems counter to these recessionary times, not only is the city's best Italian restaurant raising the cost of midweek dining, but Vetri is also shaving six seats from the townhouse dining room. At 36 before, it was already a picture of tight-squeeze intimacy.

"When people walk in and just order an appetizer and entree and then leave, they're not getting what we really set out to offer. They're not getting the whole experience," says Vetri.

The upscale moves may foretell a trend on the horizon born of pent-up desire, as other young chefs have plans to open small venues dedicated to gastronomy. Ambitious tasting menus elsewhere are also gaining new traction.

The notion seemingly flies in the face of the most recent currents, which have brought mainly trouble for "whole experience"-style fine dining, as white-tablecloth formality unraveled under the pressure of economic turmoil and a cultural shift toward more casual venues.

Walnut Street's Restaurant Row continues to crumble. Restaurant Week-style bargain menus abound year round. The Four Seasons Hotel has been exploring the potential of an independent operator for its luxurious Fountain Restaurant. And in a bid to survive two years ago, Georges Perrier's bastion of prix-fixe luxury, Le Bec-Fin, embraced an a la carte menu for the first time in its four decades, even started serving hamburgers at lunch, before announcing last year plans to finally close - moves Perrier has since reconsidered and regretted.

"I think I panicked too early and made changes I should never have done," conceded Perrier, who said his prix-fixe menus, which range from $40 to $185, are now back up to 80 percent of his meals.

Indeed, the irony is as rich as beurre blanc. Perrier's legendary restaurant, of course, began its life at 1312 Spruce St. - the townhouse address where Vetri has now ascended to the hot list of an international dinerati, which sometimes comes in from London, L.A., Chicago, or New York (not to mention Rittenhouse Square) just for dinner.

Achieving that level of fame has been a steady evolution for Vetri, a James Beard Foundation Award winner. Vetri and his business partner, Jeff Benjamin, have since opened larger casual venues (Osteria, Amis) to offer more flexible options to the salad-and-pasta crowd. Thus, the flagship has become a focal point for Vetri's dogged pursuit to craft the nation's ultimate experience in alta cucina.

New Italian china and Venetian vases have been ordered. Snazzy new uniforms for the staff ("nothing formal - but playful!") are in the works. The vestibule is being rehabbed. A new chef de cuisine, former Vetri sous Adam Leonti, is due back from a six-month kitchen stint in Bergamo. And demand for the elaborate tasting meals, with their inventive seasonal dishes and hand-painted menus, has grown over the last two years from weekends only to half of Vetri's midweek meals, when a la carte was still an option.

"This isn't the place you brought your in-laws to 12 years ago for rib-eye and broccoli rabe and spinach gnocchi," Vetri says. "You can still get that" on the tasting menu dedicated to Vetri classics. "But it's something more than that now. We're allowing evolution to happen."

Aside from the classics-menu option and the more inventive "degustazione," there will also be a pasta tasting and a vegetarian menu to choose from. And with the entire dining room tuned to the rhythm of the multicourse meals, the service, Benjamin says, should flow.

If they succeed, Vetri's seemingly contrarian moves will also make business sense. The decision to reduce seats and go all-tasting menu was partly inspired, he said, by the success of New York fine-dining icons like Del Posto and Danny Meyer's Eleven Madison Park, which cut its seats from 168 to 130, and then again to 100 - and the tune of four stars from the New York Times.

"Usually more seats equals more revenue," says Meyer, who also owns Union Square Cafe, Gramercy Tavern, and the Modern. "But if you're trying to make a restaurant more excellent, and you can't make the kitchen bigger, the only thing you can do is make the dining room smaller. It's like the teacher-to-student ratio at a school. If I can't afford to add more teachers, I need to take away students."

With the higher revenues per seat of a prix-fixe tasting, $135 vs. $100 (before tip, tax, or beverage) for an average a la carte dinner at Vetri, the restaurant can still come out ahead with fewer covers.

"If you can arrive at a formula to make the restaurant better than it was and make more money," Meyer says, "that can be a good thing for everyone."

Of course, given Vetri's elite status (with weekends booked solid two months in advance), the gambit may prove a rarefied exception to the rule in what remains a highly competitive, value-oriented restaurant market. But the business model and the push toward more ambitious gastronomy - after years of abiding the cost-conscious comfort foods, BYO bistros, and gastropubs of a meat loaf recession economy - may be gaining ground with both diners and new restaurateurs aching to splurge on repressed culinary energy.

In Jose Garces' orbit, starstruck diners piqued by his prime-time appearances on Iron Chef have been increasingly opting for high-end tasting menus, said Melissa Scully, vice president of operations. As many as 25 percent of all meals at JG Domestic and 35 percent at Tinto are tastings ranging from $65 to $85, she says.

Meanwhile, in Chestnut Hill, chef Chip Roman is readying a March opening for a new full-service restaurant with 30 seats, Mica, that will be dedicated Thursday through Sunday to multicourse tastings.

"Bigger is not better, I've found, if you're working on making the ultimate experience," Roman says. "But we cannot afford to do what we're doing today where customers come in and split a salad and an entree. Not at this level. I think Philly customers need to be retrained - they're paying for real estate."

Roman's customers have responded at his hit BYOB Blackfish in Conshohocken, with up to 40 percent a night choosing the tasting-menu option since it was introduced eight months ago.

Roman wishes others would follow suit.

"I've had this same conversation five times with [other young chefs] in the past two months," he said. "We've got a lot of guys with talent dying to show what they can do, but they're all scared of losing their pants. If everyone else is offering five courses for $35, you don't want to be the odd man out."

Perhaps the push at Vetri, where Roman himself once cooked, will lead the way.

"Hearing that Marc is doing this," he said, "definitely gives me hope."

Contact restaurant critic Craig LaBan at 215-854-2682 or claban@phillynews.com.