Lewis is a guy who has cracked 2000 yards in a season previously as well as been part of a Super Bowl team. Now, after some injuries and legal troubles he's trying to rebuild his career in Cleveland. Given the money and draft picks the Browns have invest in their OL, something that should be a massive help to a runner, can he get back to anywhere near the level he was a few years ago? My take - he could creep to 1000 yards if he stays injury free but I think the lack of passing game, or at least, a passing game that is going to be learning a lot this year (depending on which QB plays) combined with his own previous baggage sees his career continue to wind down.
I totally think that he is on his last legs and I don't see a change of scenery bringing him back to his former glory.
I don't think Cleveland has a strong enough OL for him to get 1000 yards. In the right system, I still think he will have a couple more good years in him. He was the type of back that always got better as the game went on. Now as he's getting older, that ability is slowing down.