This guy fell because he rarely has snapped to a QB under center. That seems like a small detail but it's messed up a few guys. He also has an issue with blocking at the second level. He tends to get upright and lacks leverage.
That said this is an excellent pick who will need to be coached up a little, but could play immediately if need be. Someone mentioned he was a wrestler. He was very good at it with a great record. He could have gotten a scholarship in that sport as well. This guy is tough and mean. He adds much needed ferocity to this line.
He has real football smarts and makes solid blocking calls. His motor is top drawer. Not surprisingly he's an outstanding drive blocker. His natural low center of gravity helps with leverage in tight spaces. Don't be thrown off by the negative agility comments you may see. He handles the up-the-middle seams well and rarely allows them to be split. He might be the best anchoring center in the draft.
His toughness transfers to playing injured. Incredibly, if you've had one, he actually played with a high ankle sprain. He's also played through a variety of back, shoulder and leg injuries. He's never missed a game. Once he starts he'll be there for a long time.
This guy was a team captain and his leadership skills are exemplary. He holds line mates accountable. I think he offers more than Kelly and will have a better career.