The climate change between the warm locker room and the field... 25 or 30 deg. (F), might account for 1 pound, but not 2.
Experiments show that being wet for an extended period (less than two hours) ups that to 1.7 - 1.9 PSI as the leather case stretches and relieves support of the urethane bladder. The Pats claim that their ball processing is up to about another half PSI - which would equate to about a 10 degree warming, minus delay between the buffing and the balls being submitted.
Has anyone seen an experiment with those conditions which show otherwise?
Everyone arguing that the ambient temperature caused 2 psi of deflation is ignoring the fact that the Colts balls, which were tested at the same temperature before the game, were measured and found to be still in compliance.
I think we’re roughly in agreement that 25 degrees is in the vicinity of 1 psi, more or less.
New reports I heard today is that of the 11 balls that were said to be low, only one was “2 pounds” low, and all of the others were closer to 1 pound. Can’t say if that report is accurate, as I only heard it once in passing.
What I hadn’t heard (but can well believe) is the stretching/contracting of the leather case with moisture. I could believe it, though.
As to the Pats’ mistreatment (a/k/a ball prep), the key is whether or not it heats the ball up, what that does to the internal air temperature, how long between buffing and the time they give the ball to the refs, and what the ball’s cooldown time constant is.
I’m sure the NFL has its experts working on all of these parameters. Perhaps a /S here... politics counts, too.