Forget JS' commitment for a moment, and think about his dad's, instead.
JS' family couldn't afford a personal QB trainer which so many now believe to be a prerequisite to receiving a DI offer.
Instead, his dad developed his own rudimentary (though obviously successful) training program which included such things as having him walk on his hands, and placing different colored t-shirts on a fence to simulate receivers. His dad talked about standing out there with him for hours, calling out a color and watching JS throw at the corresponding shirt.
In spite of the distinct disadvantages they faced, JS' dad relentlessly and selflessly devoted thousands of hours - despite never knowing if it would ultimately prove to be successful, or of any benefit whatsoever.
With so much uncertainty in what his effort might bring, one has to wonder how his dad continued to expend those thousands of hours, hanging those shirts on that fence, calling out colors, and shagging balls for him. And not just once mind you, but day after day after day. Long before anyone dreamt about a "4*" ranking, an ESPN announcement at Disneyland, or an 8,000 post thread bearing his son's name from a group of strangers mostly residing a continent away, JS's dad was out there, calling out the colors of shirts hung on a chainlink fence.
The man, acting out of love for his son, wanted to be certain that he gave JS every possible opportunity for the greatest success, to the best of his ability to provide it, however limited or ineffective it may ultimately prove to be. Simply, he did it to be sure that JS was given a shot.
I can't imagine how difficult it would be for his dad to see the fruits of those many hours of labor finally being rewarded.....only to see it take his son some 3,000 miles away in order to realize the very opportunity which you've worked so selflessly to provide. It would suck on many levels, to be sure.
However, do you know what would suck even more? Driving 20 minutes too see those efforts go unrealized, and the opportunity not simply being lost, but unprovided.
Think about it:
Would you feel better knowing that he would be met with both adoring and open arms, though 3,000 miles away -OR - that he would be but one of the many faceless others, but only 20 minutes away?
Were he my son, I'd prefer to see him get the opportunity which I have so diligently striven to provide, amongst those who wanted and needed him, despite the distance that such entailed.
Conversely, the fear of seeing it all go unfulfilled amongst those seemingly ambivalent to either your presence or absence would be the truly hellish nightmare, if you ask me. The fact that it would occur some 20 minutes away would only make it so much the worse to experience.
JS' dad loves him, and wants what is best for him. For those simple reasons alone, I am not sold that he is, "against" JS' committing to Tennessee, nor even that it is inevitable that he signs with USC.