Per your first part, you are right and wrong. You can jam a receiver 5 yards from scrimmage is where you are right. You are wrong that it is just 5 yards, those are pro rules. In college you can be handsy until the ball is in the air no matter the distance.
So Cyclone offensive lineman Ben Bruns in depth analysis displays more in depth knowledge of the game than ref apologist @cycloneML.
It was definitely before a pass. His larger point was that among the things that could be called, unnecessary roughness was one of the things that made the least sense.