Days has more problems than speed to be an affective rb in the nfl. He got better at it as the season went along, but he was falling down anticipating being tackled before he was being hit, so he was falling forward when he could have possibly gotten more yards. Days also doesn't pick his legs up very much, lynch has very high knees when he runs which gives you much more power when running. Another thing that days does not have is an elusiveness about him which all top rbs have. I'm not so sure this would be a problem with days but playing rb is a lot different than bback because at bback you are hitting the hole so hard and it's not as much reading till you get to the line of scrimmage, at running back you are further back so when you get the ball you aren't at the line of scrimage and you need to have good vision to be able to make cuts at the line of scrimage, I say I'm not sure that will be a problem with days because he had decent vision when he got through the line of scrimage although it still is different.