Oh, YES, we would notice. We can throw balls further which are under-inflated.
Also, the few other experiments and simulations both that have been done show that the difference for 2.0 PSI (Far larger a difference than any actual 2014 AFCCG footballs) a 20 yard throw is in the opposite direction (shorter), and less than two inches. So, he’d need to explain that.
Here’s an example from Sports Science, which falls well within the other test results: https://www.youtube.com/watch?v=TSJNsGUSAJ8
“Really?”
Yes, really. I was not going by any scientific experiments. I was simply stating that I could throw a ball further when it was under-inflated. It is a simple matter of the ball not being as slippery and the grip was better for me which made it easier to throw further. It also had to do with, again, the point of the ball not being as slippery, hence I could throw it further by about 10 yards when I had my index finger on the point of the ball.....using an NFL Duke ball.
It is interesting to note, however, that prior to the merger, the American Football League ball was slimmer and slightly longer which made it much easier to throw and for those two reasons is could be thrown further.
Your results may vary.