That stuff about Jones being 'lazy' and sometimes 'unmotivated' seemed completely dead on accurate to me.
Jones best running comes when he is motivated, determined, and on a mission. See his rookie year and the Seattle game, when he dominated. He seems to have a mentality in those instances of 'I am not going down, everything I have is going into this run." When that happens, he is fantastic.
Unfortunately, he often doesn't seem to be that fiery, like last season. I don't think he is particularly weak when it comes to breaking tackles. Disinterested isn't the word, either. More of a matter of - he isn't putting every last thing he has into staying upright, and in the NFL, you have to.
If Jones could be motivated in everygame, he would look like his talent indicates. Unfortunately, it's all in the brain, not in the body.