[jsyedidia]

The reason that they didn't correct the pressure at game-time is that after the Patriots give the balls to the referees 2 hours and 15 minutes before game time, they are not allowed to touch them, and the refs do not have the procedure of re-checking them and correcting them. I imagine that there might be a rules or procedure change so that they do, and as early as the Super Bowl.

The "evidence" for my explanation is the ideal gas law and what Belichick said his team did in his press conference today. If the Patriots followed that procedure, which there is no reason to believe they didn't, and which is legal, one expects from the ideal gas law that their balls would seem under-inflated at half-time. It's basic physics and easy to understand theoretically and reproduce experimentally.

My speculation for what the Colts did rests on the reports that their balls did not deflate. For that to hold, given the laws of physics, something like the balls equilibrating to the outdoors temperatures before giving them to the refs must have happened.