[newfreep]

Just simple physics - one can more easily squeeze vs a fully inflated that is larger, harder and less “gripable.

Anyone who has played street football or even just passing it would grasp that reality.

It’s not rocket science...

[Bloody Sam Roberts]

No, it's not rocket science. It is simple physics as you said. And as such, developing technique and muscle memory using a specific object and becoming proficient at it...then expecting better results using an object that performs differently in the hand seems odd.

Now...I would definitely expect under inflation to benefit the receiver somewhat but how much of an advantage would that be if the ball is delivered off target because the QB is not used to using a ball in that state?

Does an under inflated ball behave differently? No one except a Pro QB can say for sure. I have played organized football and even played QB for a time. I only base my guesses on experience in handling a football. I'll wait for the investigation to complete before passing any judgement.