Which is why I always say, that in many cases, it's situations that dictate running success, and NFL RB's are largely "plug and play" outside of an elite few.
Look at Cedric Benson. Guy underwhelms his entire career, goes to the Bengals last year and has a big statistical season. Anyone who watched the Bengals last year knows that they were probably the best run blocking team in the league. Benson had a bunch of long runs where he wasnt touched for 10-12 yards. He was the same bum he always was, with no outstanding attributes...he's not fast, isnt elusive, isnt particularly strong or hard to bring down...he's just a guy. Fanatsy geeks and other assorted fans were convinced he was one of the best backs in the league. Bernard Scott would have done the similar things with the same opportunities.
You have a about 8 guys who clearly stand above all others, and a bunch of guys on the bottom of rosters who arent very good. In between, you have the majority of the leagues backs who are largely interchangable and products of situation and opportunity.
What any of this has to do with LT im not sure.