Just don't say they supersized it, but Burger King (BKW.DL) has made its Big Mac knockoff, the Big King, even bigger.

In recent years, Burger King has pulled out all the stops to battle competition from other fast food chains, fast casual restaurants, and people simply choosing to not eat out. It's latest "innovation," however, takes clear aim it its historical nemesis, McDonald's (MCD -0.42%).

Using the hasn't-been-clever-since-1983 tag line, "Burger King knows that size matters," the company has introduced the bigger Big King.The company is not specific as to exactly how much bigger the new sandwich, which is essentially the Big Mac without a pickle, is, simply calling it "even bigger" and "beefed up" in the launch press release.

The move is the latest in a series that has seen Burger King launch everything from ribs, to a sandwich topped with french fries, bacon sundaes, and lower-calorie fries.

Is all this new stuff working?

McDonald's, the world's No. 1 fast-food chain, reported weaker-than-expected quarterly sales at established restaurants last month as fewer diners visited its restaurants. In contrast, Burger King reported a 1.7% rise in systemwide comparable sales for the fourth quarter ended Dec. 31.

Burger King credits its new additions, specifically the Big King and Satisfries, with helping it achieve better numbers

"During Q4, the introduction of the Big King sandwich and the first full quarter of Satisfries, a first of its kind better-for-you french fry, helped increase sales.  In addition, we added the BBQ Rib Sandwich to help drive incremental traffic in the value tier," said the company in its Q4 report. 

What's in a sandwich?

If you remember the old jingle, a Big Mac features, "two all-beef patties, Special Sauce, lettuce, cheese, pickles, onions on a sesame seed bun," you pretty much know what's on the Big King. "The beefed up sandwich features two savory fire-grilled beef patties, freshly cut lettuce, crisp onions, and signature King Sauce, all on a three-layer warm, toasted, sesame seed bun," said Burger King in a press release touting the launch.Yes, Burger King even stole the weird, extra middle bun from the Big Mac, which theoretically makes the two skimpy patties look more impressive.

Though fast food companies do tend to copy each other's successes, the Big King seems especially egregious because Burger King already has its own signature sandwich, the Whopper, which actually predates the Big Mac. The Big King is a copy of the Big Mac, which is a copy of The Whopper, which was always made with a quarter pound of beef as the new bigger, Big King is (though the company won't confirm that). 

Slowing it down

While Burger King has fought its way back to sales growth by introducing a slew of new products, Alexandre Macedo, president of Burger King North America, told Nation's Restaurant News that going forward, the company would focus on "fewer, more impactful" product launches resulted from a mutual interest from both the franchisee community and the company.

This goes against common fast food industry logic where new and revamped products (like making something spicy or adding bacon) has generally been the path to success. The slower approach, Macedo said, will let the company get more attention when it changes its menu.

"Everyone in the country knew we were launching Satisfries," he said, "and it's the same thing we want to do moving forward."

Is being too much like McDonald's a fear?

It's not just the Big King that's a direct poke (or blatant copy, depending how you look at it) at its bigger rival; other recent product launches have felt a lot like copycat moves. The Rib Sandwich is essentially a McRib and its Chipotle Chicken Wrap clearly owes quite a bit to the McWrap.

Of course, Burger King has not exactly tried to hide its knockoff strategy. The ads for its BK Breakfast Muffin Sandwich, actually show the King character breaking into McDonald's to steal the recipe for the Sausage McMuffin with egg. (Why would there need to be recipe for a product that's an English muffin, an egg, a sausage patty, and a slice of cheese?)

Will it work?

While the strategy of copying McDonald's seems to have been successful in the short term, it's hard to believe customers will flock to a chain that builds its identity around selling sort of, kind of, what its main competitor does. Building off the success of Satisfries -- which were a truly novel idea -- seems more likely to attract sustained customer interest.

Finding the next pretzel bun craze or creating a new shape to press chicken into that will somehow get kids excited can give Burger King its own brand. Launching versions of McDonald's products that substitute a word or a few letters in the name seems a little silly, no matter how big they make the burger.