I'm not speculating based one one game as you say... He missed last week, and has looked like shit all preseason and week one. Not to mention how his numbers took a nosedive last year. If not for that Denver game in week 17 last year he would have had under 10 rushing TDs (never happened before, not even as a rookie) and would have had a whopping 1014 rushing yards.. He had TWO games over 100 yards rushing last year, 2!
Not to mention the guy has been a total bust in the playoffs topping 100 yards only once (in a loss to NE), and gaining a fantastic 303 yards and 4 TDs over 6 games. But he was gaining an average of 3.61 yards per carry so I guess he was a stud..
And anyone who has watched the Chargers over the last 5 years and is honest with themselves will tell you that the LT of last year and thus far this season has not looked like the LT of old. He can't make the same cuts that he used to that would destroy a defense and he is nowhere near as physical as he was before.