I am not sure id call them knocks when they dont affect his play or show up on tape.
In Johnson's case it is a plus / positive that he is raw and new to the LT position as he did very well there and held his own against some of the top pas rushers in the NCAA last season.
Obviously you would want I guy that has produced at said position for awhile but you cant always get that. He produced when given the chance and that is all you can ask for.
Knocks are knocks dude, there's a reason he was only an honorable mention in the big 12. He just doesn't standout like the other tackles in the first, and I do not want my new LT to be raw or just trying out LT for the second time, and only his second year already facing the best in the NFL.
Him having a good game against Moore is the only positive right now besides 'potential'.