Do you toss and turn at night wondering how CBS can run promos proclaiming its new James Woods drama, "Shark," the season's most watched new series, and "CSI" the most watched show, when NBC's new "Heroes" is clocking about a million more viewers than "Shark" and Tuesday's "American Idol" on Fox posts about 15 million more viewers than "CSI"?

Never fear, we're here to help you get a good night's sleep by explaining this outbreak of apparent TV industry horseradish:

Through last Sunday, "Heroes" is averaging about 14.5 million viewers to "Shark's" 13.4 mil.

You and I might say that makes "Heroes" the season's most watched new show. Number-crunching Nielsen Media Research feels otherwise.

CBS explains:

"According to Nielsen, claims of 'most watched' can only be made based on gross impressions, which is number of telecasts multiplied by the program's average audience," the network said in a statement sent to The TV Column.

"In the case of 'Shark,' it's based on 20 broadcasts multiplied by its average audience of 13.37 million viewers, which equals 267.38 million gross impressions, more than any other new series," the network said.

"Heroes," on the other hand, had aired only 15 times through last weekend, which, when multiplied by its season average of 14.5 million viewers, works out to about 217 million gross impressions.

It's this same kind of big picture, out-of-the-box thinking that makes "CSI" the season's most watched series though it's eating "Idol's" dust each week.

"CSI" has been on since September. Its season average of 20.6 million viewers therefore gets multiplied by 20 episodes for a grand total of 412 million gross impressions.

Through last weekend, "American Idol" had aired only four times on Tuesdays, for instance. This means its Tuesday average audience -- a whopping 35.3 million viewers -- gets multiplied by just 4. This leaves "Idol" with a measly 141 gross impressions on Tuesday nights.

Now, some people at one network -- extra credit for correctly guessing which one -- note that a little clause in the Nielsen National Reference Supplement issued for the 2006-07 TV season tells network suits the expression "most watched" "should not compare individual programs with significant disparity in the number of telecasts."

Execs at other networks have discussed the CBS promos with Nielsen. Nielsen, they say, is sticking by its guns.

On the other hand, if NBC wants to run a promo declaring "Heroes" the No. 1 new series or the highest-rated new series, it could certainly do that. Ditto Fox, should it feel moved to air promos crowning "American Idol" TV's No. 1 show.

"There's something here for everyone," Nielsen spokesman Jack Loftus told The TV Column.

Shockingly, neither promotion may come to pass.

One of the deeper-thought thinkers at one of those networks explained they've dismissed the CBS promos as "just another form of [flagpole] waving." The executive did not want to be identified because he did not want to acknowledge he'd given a moment's thought to the CBS promos.

Some non-CBS execs even suggested optimistically the CBS promos could make the network sound foolish because, they insisted, most people realize more people are watching "American Idol" than any other program and that "Heroes" is topping the heap of new series.