Last October, I wrote about some of the problems the Titans were having in the run game. The point of that post was that the Titans were having problems running up the middle, but those problems weren't new from the Titans' more effective rushing attack in 2009. Rather, the problems the Titans had in 2010 came from being less effective running outside, particularly to the right side. Much changed for the Titans the second half of the season, but those problems running outside to the right continued, and the Titans were still ineffective running up the middle.
The most interesting question, which I addressed in part but not wholly in that post, is why that happened, and why the Titans couldn't fix the problem. The departure of Alge Crumpler, and Bo Scaife's difficulty blocking certainly played a role. There were a couple other causes that I didn't address in that post that also played a role.