Baseline: why hype up a true freshman at a position that freshman struggle at? OL is a developmental position. I don't care how many stars you have: it is VERY rare for a true freshman to contribute there, especially at tackle. The jump from HS to the SEC is massive, as you go up against guys who are 300 lb but move like a freight train, along with those who are 240 and will just run right around you on the edge. You have to not just be physically gifted, but have the right mix of strength, weight, and speed to succeed there. Most successful college teams have RS JR and SR OL.
For Sanders: the rumor mill is that he had a stinger, but is showing arm weakness, meaning he has pinched a nerve. This is a serious injury if not given the appropriate time to heal, as continued stress on a nerve from a bulging disc can cause longterm nerve damage. Depending on the location, it can be a lot of PT to reduce the threat of bulging happening again. Also, having experienced this myself, you lose a surprising amount of arm strength when the wrong nerve is pinched. I was unable to hold up more than 10 lbs for 4 weeks until it started getting better.