This won't go away. It's awful, it's terrible, it's clutching at straws, and it's an entirely manufactured controversy.
There won't be a penalty. There can't be.
This is at least the third time this season that modifying the football has become a story. The prior two times had zero repercussions (and both coincidentally took place on November 30th).
First, the Minnesota Vikings were blamed for warming up the football on a cold day, which is explicitly forbidden by the rule book. The outcome? The NFL was "aware", the Vikings weren't notified of any special league research, and a memo was circulated to the league to stop warming footballs when it's cold outside.
That's it.
On the same day, the Patriots were playing the Packers and the commentators, Jim Nantz and Phil Simms, talked about how Aaron Rodgers told them that he overinflated the football to try and get past the referees.
Nantz: We talked to [Aaron] Rodgers about 'How do you like your footballs?' Because, you know, you can rub them up before the game. [Phil], you really kind of created that for everybody else in the league.
Simms: I don’t know if I did, because the quarterbacks got tired of them complaining. But he said something [that] was unique: 'I like to push the limit to how much air we can put in the football, even go over what they allow you to do and see if the officials take air out of it.' Because he thinks it’s easier for him to grip. He likes them tight. Of course, he’s got very big hands and you can tell that by watching him play.
Here's audio from the game (from Sons of Sam Horn).
Nothing happened. That was the whole situation. No investigation followed.
Keep in mind that there has been zero proof of any wrongdoing by the Patriots. All that's out there is a question by a Colts defender about the ball's weight, and a standard number of underflated footballs being removed from the sideline (and to repeat: it's normal for footballs to be removed from the sideline).
This is another case of other teams doing exactly what the Patriots are being accused of, yet only New England is brought under the microscope.