If you don't know what you are talking about, STFU.
You can't be interferred with, unless you are trying to make a play on the ball. If you aren't making a play on the ball, you cannot impede another playing who is. Simply, and easy. On the touchdown play, Marks did not interfere when he pushed off the defender because the UCLA defender wasn't trying to catch the ball, as evidenced by the fact he had his back to the ball. Had he turned around and was making a play on the ball, a push off would have been a foul. But in the real world, the defender was doing everything in his power to impede Marks from catching the ball, and Marks had every right to push back to make a play.
It is your job to know the single most important rule in the game of modern football.
You can't be interferred with, unless you are trying to make a play on the ball. If you aren't making a play on the ball, you cannot impede another playing who is. Simply, and easy. On the touchdown play, Marks did not interfere when he pushed off the defender because the UCLA defender wasn't trying to catch the ball, as evidenced by the fact he had his back to the ball. Had he turned around and was making a play on the ball, a push off would have been a foul. But in the real world, the defender was doing everything in his power to impede Marks from catching the ball, and Marks had every right to push back to make a play.
It is your job to know the single most important rule in the game of modern football.