The most frustrating part of this entire discussion to me is that BB and the Patriots actually REPLICATED the conditions, and reported the results.
How could? What if? and why? questions about what happened are pointless without this context.
The Patriots prepped the balls, raising the pis 1 to 1.5 lbs. The Patriots handed the balls to the refs after being prepped (up 1-1.5) and having been stored at indoor temperatures. The effect of bringing them outside is another .5 to 1 psi.
BOTH OF THESE EFFECTS ARE TEMPORARY, AND AS THE BALLS STABILIZES FROM PREPARATION AND WARMS BACK TO ROOM TEMP, THEY GO AWAY.
The Patriots prepare the footballs, on game day, and hand them to the refs in the state where they are temporarily over pressurized by preparation and are at room temp.
Lets assume they are 12.5.
If the balls sat in the room for a few hours, they would drop to 11 to 11.5 (normalizing from the preparation).
If they are taken outside they will now drop another .5 to 1 pound and be anywhere from 10 to 11.
When they are return inside they will warm to 11 to 11.5 but never again reach the 12.5 that the refs measured (if they did) because the effect of prep is gone forever.
The Colts balls were prepped in Indy (I cant fathom why they would do it here). So the Patriots footballs and the Colts footballs will differ in deflation by 1 to 1.5 psi because of the effect of preparation. Since the balls are delivered to the refs 2:15 before kickoff, we do not know where they were stored, so we do not know whether the effect of being taken into the cold would apply.
Patriots footballs if started at 12.5 will be 11 to 11.5
Colts if started from 12.5 to 13.5 would be either 12.5 to 13.5 if started cold, or 11.5 to 13 if started from warm.
As far as the second half footballs, that is very easy to explain as well.
These balls by the time the game was over had return to 'pre-prep' equilibirum, and inflated to whatever the refs did, and had been in the cold already, so had neither effect (prep or cold) impacting them, so they would have measured the same before and after.
This is incontroverible logic if taken with the results of a field test to replicate conditions that BB did.
It cannot be disproven without a separate field test to show BBs findings are wrong, and they would have to be drastically wrong.