Have you ever tried to tear through the margin of a t-shirt? It isn't easy. It's very easy to tear through the body of the t-shirt- once you get past the margin. But that margin, that molding around the opening, is tough material, and it's hard to rip it.
It's hard even when you position it to greatest advantage. But, in that altercation at the theater, the cops weren't trying to rip his t-shirt. If it got ripped, it was accidental.
So, just as an experiment, take out a t-shirt, a round t-shirt, and grasp the margin between your two hands and try to tear it. Increase the effort slowly, but I think you will find that you can apply quite a lot of force without it tearing. You may find that you can't break it open no matter how hard you try.
But, it's not really a fair test because you're doing it concertedly, and the cops were doing no such thing.
Let's say a cop grabs Oswald by the t-shirt. It seems unlikely because Oswald did have his outer shirt on at the theater. But, we'll assume it anyway. So, the cop is gripping the t-shirt, and he pulls on it to pull Oswald to him. He is trying to control him, to dominate him, and he does that by pulling him in.
So, he pulls on the t-shirt, which has give, and so it stretches. But, it only stretches so far before the force he is applying gets transferred to Oswald himself. In other words, he accomplishes what he set out to do, which is to move Oswald toward him, to reel him in. Once Oswald starts moving, the policeman's force is transferred through the t-shirt to Oswald himself, and Oswald's movement absorbs the force of the policeman's effort.
So, in effect, the t-shirt is acting like a rope or a tie. The cop pulls on the t-shirt to the point of tension, and from that point on, the force gets transferred to Oswald, which is the whole idea.
It is very unlikely that the margin of the t-shirt would tear because the force isn't being concentrated there.
If the cop were pulling on Oswald's shirt and Oswald was immobile, then the force wouldn't pass through- it would remain with the t-shirt. And then it probably would tear.
I saw footage of two jackals chasing a young gazelle. They reached it at the same time. One got his jaws around one leg, the other jawed the other leg; and then they went in different directions. And they tore that young gazelle in half! But, if it had been just one jackal, he wouldn't have torn the gazelle in half because when he pulled, there would have been no resistance, and the young gazelle would have moved with him and remained intact.
So, unless you think there was one cop pulling one way on Oswald's t-shirt and another cop pulling another way on Oswald's t-shirt at the same time, there is no reason to think the margin of the t-shirt was torn through. But, how could that happen when most of the t-shirt was covered up by Oswald's outer shirt?
Oswald's t-shirt was tattered from wear, but the margin was intact.
I see the disruption on his left side. That's threadbareness from wear; it's not the result of violence. It was a very old, tattered t-shirt. But again, those defects are irrelevant to what the margin is doing because the margin, as you can see, is intact.