In this wacky, topsy-turvy biz we call television, the one constant has been the NFL. It brings in the viewers and helps bring them back for other programming. The ad dollars pile up at a predictable rate. Until this season. From the start, the NFL and its TV distributors have noticed the ratings have not been measuring up to last season. On Wednesday, Nielsen ratings cruncher Brian Wieser of Pivotal Research Group published a report that concludes that viewership among adults 18-49, live plus same day, is off 15.1%. The big question is why. And it's just not the NFL...