NEW YORK – “American Idol,” for all its success, is not above tinkering – especially after last year’s revolving door of celebrity mentors and Sanjaya Malakar’s improbable run.

Not TOO much tinkering, though. Why mess with a trusty formula?

The Fox ratings superpower returns for its seventh season on Tuesday, and will doubtless dominate January through May as it did last year and the year before that. It could even attract a bigger audience in 2008, thanks to the Hollywood writers strike.

But Nigel Lythgoe, an executive producer for the show, downplayed speculation that the lack of alternative programming as a result of the strike could equal more viewers for “Idol.”

“Everyone is sort of saying that there isn’t anything else on television to watch,” Lythgoe told The Associated Press.

But the other networks are so intimidated by the most-watched show on American television that “they don’t really schedule anything around ‘Idol’ anyway,” he added.

“American Idol” has reached a plateau in the ratings, down only 1 percent from 2006 (30.7 million average viewers) to 2007 (30.4 million). The finale with winner Jordin Sparks was seen by 31.2 million, according to Nielsen Media Research.

That fell below the 2006 season-ender, which drew 36.6 million viewers watching Taylor Hicks claim the title in an unpredictable matchup with Katharine McPhee.

Lythgoe acknowledged that the show suffered last year when finalists failed to top the excitement and star quality of performers from previous seasons; on the other hand, he said producers erred by giving too much air time to famous mentors like Jennifer Lopez with individual projects to promote rather than delving deep into contestants’ back stories to foster a stronger connection with viewers.

“We felt as though we made mistakes last year with not really pushing and introducing the talent as well as we have done in the past,” he said. “In the past, we knew about (season five also-ran) Kellie Pickler. We knew about her dad going to prison. We knew about her mom leaving (the country singer when she was a toddler).”

(Blake Lewis, we hardly knew ye.)

This time around, the show will redirect attention to the finalists and bring back alums such as McPhee and season-two winner Ruben Studdard during results shows to keep fans abreast of what they’re up to, Lythgoe said. There will be a new set to spice up a tried-and-true format.

“The most important thing is the show has got to look better,” Simon Cowell said during a recent telephone news conference. “It’s got to be more fun as a show, and if it is, I think more people will watch. I think it absolutely comes down to the content of what we provide the viewers.”

The new season kicks off with two-hour episodes airing 8-10 p.m. EST Tuesday and Wednesday and featuring auditions in Philadelphia and Dallas, respectively. Another tweak: “Idol” wannabes were allowed to play instruments during tryouts.

Of course, the voice is what matters most – and charisma, the reason why the vocally challenged Sanjayas of the world advance further than they otherwise should.

Of course, charisma doesn’t always translate to commercial success after the contest crowns its final winner.

Hicks, Studdard and McPhee have lost record deals with Sony-BMG, which automatically signs the show’s singers. Hicks’ self-titled, post-“Idol” album has sold a respectable 699,000 copies, according to Nielsen SoundScan, but it did not reach the 1 million mark surpassed by debuts from previous “Idol” champs. Studdard’s previous album, 2006’s “The Return,” has sold only 236,000 copies.

Sparks’ freshman disc has sold 425,000 units since its November release, and has spawned a hit single with “Tattoo.”

Meanwhile, multiplatinum “Idol” veterans such as Kelly Clarkson, Carrie Underwood and Chris Daughtry – who laughed all the way to the top of the charts after finishing fourth to Hicks – can be heard on the radio at any given moment of the day.