Does it really matter as long as the games aren't on a conventional workday or interfere with college games?
Per the article, it doesn't matter.
But the NFL is now big enough to overcome traditions. The NFL is big enough to make new traditions. And the evolving tradition is this — during football season, any day is Sunday. Every day is Sunday. The audience will be there, whenever and wherever NFL games are played.
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As Jerry Jones said in March, "When the duck quack, feed 'em." The ducks currently prefer getting their meals more often than to having an all-you-can-eat brunch on Sunday at 1:00 p.m. ET.
With no real competition from network TV on Sunday, Monday, Tuesday, Wednesday, and Thursday night, why not keep the ducks fat and happy from Labor Day through Week 18?
but that wouldn't work for a variety of reasons.