More than 40 million people watched the NFL’s two preliminaries for the Super Bowl on Sunday, a drop of more than 8 percent compared to last year’s conference championship games. The Nielsen company said an average of 43.2 million people watched the games. While that’s down from the 47.1 million who watched the conference championships last year, it was a more heartening report than the NFL had gotten only a week earlier. This year’s divisional championship round had seen a 16 percent dip in audience size. […] After seeing viewership erosion all year, the NFL will be anxious to see...